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51. Impulsive and long duration high-energy gamma-ray emission from the very bright 2012 march 7 solar flares

Author: T. Jogler, Nicola Omodei, Luca Latronico, Charles D. Dermer, M. Tinivella, E. Do Couto E Silva, Denis Bastieri, G. Pivato, Vahé Petrosian, E. J. Siskind, Johann Cohen-Tanugi, Hiromitsu Takahashi, J. Lande, M. E. Monzani, R. J. Murphy, M. Brigida, Elisabetta Bissaldi, R. Buehler, Brian L Winer, E. Orlando, Stefano Ciprini, Jürgen Knödlseder, J. H. Panetta, T. Glanzman, Alice Allafort, Yoshiyuki Inoue, J. S. Perkins, Seth Digel, Dario Gasparrini, W. N. Johnson, F. Piron, A. A. Moiseev, Masanori Ohno, Nicola Giglietto, Ronaldo Bellazzini, Paolo Giommi, J. F. Ormes, André Schulz, Rodrigo Nemmen, T. Ohsugi, Eleonora Troja, Julie McEnery, Miranda Jackson, D. Horan, S. Murgia, Emanuele Bonamente, G. A. Caliandro, I. A. Grenier, A. Reimer, A. Chekhtman, Peter F. Michelson, Marcello Giroletti, S. Larsson, Alex Drlica-Wagner, F. Loparco, Gudlaugur Johannesson, X. Hou, G. Tosti, Daniela Hadasch, W. B. Focke, M. Hayashida, P. Spinelli, F. Gargano, Gloria Spandre, Justin Vandenbroucke, Benoit Lott, M. Roth, M. Mayer, M. Razzano, Giacomo Vianello, Melissa Pesce-Rollins, Filippo D'Ammando, Francesco Giordano, Marco Ajello, R. E. Hughes, Guido Barbiellini, J. B. Thayer, M. N. Lovellette, P. A. Caraveo, R. Desiante, T. J. Brandt, Persis S. Drell, D. L. Wood, L. R. Cominsky, Zhenwei Yang, Igor V. Moskalenko, R. A. Cameron, Francesco Longo, T. Kamae, T. A. Porter, Michael David Werner, E. Hays, M. Orienti, V. Vasileiou, D. Paneque, Olaf Reimer, D. J. Thompson, P. Fusco, P. Bruel, Carmelo Sgrò, Riccardo Rando, Jan Conrad, S. Buson, G. Godfrey, R. Claus, T. L. Usher, A. Morselli, V. Vitale, L. Tibaldo, E. Nuss, C. Monte, C. Favuzzi, J. Bregeon, D. Kocevski, F. de Palma, S. Rainò, Tsunefumi Mizuno, M. Kuss, Takeshi Nakamori, A. S. Johnson, S. Cutini, G. Chiaro, J. E. Grove, Yasushi Fukazawa, Andrea Albert, S. Germani, K. S. Wood, James Chiang, A. Franckowiak, Luca Baldini, J. G. Thayer, M. N. Mazziotta, Sylvain Guiriec, Claudia Cecchi, Eric Charles, P. Lubrano, Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire Univers et Particules de Montpellier (LUPM), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Ajello M, Albert A, Allafort A, Baldini L, Barbiellini G, Bastieri D, Bellazzini R, Bissaldi E, Bonamente E, Brandt TJ, Bregeon J, Brigida M, Bruel P, Buehler R, Buson S, Caliandro GA, Cameron RA, Caraveo PA, Cecchi C, Charles E, Chekhtman A, Chiang J, Chiaro G, Ciprini S, Claus R, Cohen-Tanugi J, Cominsky LR, Conrad J, Cutini S, DAmmando F, de Palma F, Dermer CD, Desiante R, Digel SW, Silva EDE, Drell PS, Drlica-Wagner A, Favuzzi C, Focke WB, Franckowiak A, Fukazawa Y, Fusco P, Gargano F, Gasparrini D, Germani S, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grenier IA, Grove JE, Guiriec S, Hadasch D, Hayashida M, Hays E, Horan D, Hou X, Hughes RE, Inoue Y, Jackson MS, Jogler T, Johannesson G, Johnson AS, Johnson WN, Kamae T, Knodlseder J, Kocevski D, Kuss M, Lande J, Larsson S, Latronico L, Longo F, Loparco F, Lott B, Lovellette MN, Lubrano P, Mayer M, Mazziotta MN, McEnery JE, Michelson PF, Mizuno T, Moiseev AA, Monte C, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Murphy R, Nakamori T, Nemmen R, Nuss E, Ohno M, Ohsugi T, Omodei N, Orienti M, Orlando E, Ormes JF, Paneque D, Panetta JH, Perkins JS, Pesce-Rollins M, Petrosian V, Piron F, Pivato G, Porter TA, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Roth M, Schulz A, Sgro C, Siskind EJ, Spandre G, Spinelli P, Takahashi H, Thayer JG, Thayer JB, Thompson DJ, Tibaldo L, Tinivella M, Tosti G, Troja E, Usher TL, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Werner M, Winer BL, Wood DL, Wood KS, Yang Z, Ajello, M., Albert, A., Allafort, A., Baldini, L., BARBIELLINI AMIDEI, Guido, Bastieri, D., Bellazzini, R., Bissaldi, Elisabetta, Bonamente, E., Brandt, T. J., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Cecchi, C., Charles, E., Chekhtman, A., Chiang, J., Chiaro, G., Ciprini, S., Claus, R., Cohen Tanugi, J., Cominsky, L. R., Conrad, J., Cutini, S., D'Ammando, F., De Palma, F., Dermer, C. D., Desiante, R., Digel, S. W., Do Couto E. Silva, E., Drell, P. S., Drlica Wagner, A., Favuzzi, C., Focke, W. B., Franckowiak, A., Fukazawa, Y., Fusco, P., Gargano, F., Gasparrini, D., Germani, S., Giglietto, N., Giommi, P., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Grove, J. E., Guiriec, S., Hadasch, D., Hayashida, M., Hays, E., Horan, D., Hou, X., Hughes, R. E., Inoue, Y., Jackson, M. S., Jogler, T., Jóhannesson, G., Johnson, A. S., Johnson, W. N., Kamae, T., Knödlseder, J., Kocevski, D., Kuss, M., Lande, J., Larsson, S., Latronico, L., Longo, Francesco, Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Mayer, M., Mazziotta, M. N., Mcenery, J. E., Michelson, P. F., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Murphy, R., Nakamori, T., Nemmen, R., Nuss, E., Ohno, M., Ohsugi, T., Omodei, N., Orienti, M., Orlando, E., Ormes, J. F., Paneque, D., Panetta, J. H., Perkins, J. S., Pesce Rollins, M., Petrosian, V., Piron, F., Pivato, G., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Reimer, A., Reimer, O., Roth, M., Schulz, A., Sgrò, C., Siskind, E. J., Spandre, G., Spinelli, P., Takahashi, H., Thayer, J. G., Thayer, J. B., Thompson, D. J., Tibaldo, L., Tinivella, M., Tosti, G., Troja, E., Usher, T. L., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Werner, M., Winer, B. L., Wood, D. L., Wood, K. S., and Yang, Z.
Subjects: Sun: flares, [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Proton, Astrophysics::High Energy Astrophysical Phenomena, Hadron, Astrophysics, Sun: X-rays, gamma rays, 7. Clean energy, 01 natural sciences, Power law, Spectral line, flares, Sun: X-rays, gamma rays [Sun], 0103 physical sciences, Coronal mass ejection, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Physics, Sun: flare, Solar flare, 010308 nuclear & particles physics, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Sun: flares, Sun: X-rays, gamma rays, Gamma ray, Astronomy and Astrophysics, gamma rays, 13. Climate action, Space and Planetary Science, Physics::Space Physics, ddc:520, Astrophysics - High Energy Astrophysical Phenomena, Sun: X-rays, Fermi Gamma-ray Space Telescope
Abstract: The Fermi Large Area Telescope (LAT) observed two bright X-class solar flares on 2012 March 7, and detected gamma-rays up to 4 GeV. We detected gamma-rays both during the impulsive and temporally-extended emission phases, with emission above 100 MeV lasting for approximately 20 hours. Accurate localization of the gamma-ray production site(s) coincide with the solar active region from which X-ray emissions associated with these flares originated. Our analysis of the >100 MeV gamma-ray emission shows a relatively rapid monotonic decrease in flux during the first hour of the impulsive phase, and a much slower, almost monotonic decrease in flux for the next 20 hours. The spectra can be adequately described by a power law with a high energy exponential cutoff, or as resulting from the decay of neutral pions produced by accelerated protons and ions with an isotropic power-law energy distribution. The required proton spectrum has a number index ~3, with minor variations during the impulsive phase, while during the temporally extended phase the spectrum softens monotonically, starting with index ~4. The >30 MeV proton flux and spectra observed near the Earth by the GOES satellites also show a monotonic flux decrease and spectral softening during the extended phase, but with a harder spectrum, with index ~3. Based on the Fermi-LAT and GOES observations of the flux and spectral evolution of these bright flares, we explore the relative merits of prompt and continuous acceleration scenarios, hadronic and leptonic emission processes, and acceleration at the solar corona by the fast Coronal Mass Ejections (CME) as explanations for the observations. We conclude that the most likely scenario is continuous acceleration of protons in the solar corona which penetrate the lower solar atmosphere and produce pions that decay into gamma-rays., Comment: Contact Authors: N. Omodei, M. Pesce-Rollins, V. Petrosian. 14 pages, 5 figures, 4 Tables. Submitted to The Astrophysical Journal
Published: 2014
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52. Test of Models of the Cosmic Infrared Background with Multiwavelength Observations of the Blazar 1ES 1218+30.4 in 2009

Author: Wystan Benbow, Daniel Nieto, A. N. Otte, M. P. Connolly, A. Bouvier, L. Ciupik, R. Dickherber, Geza Gyuk, T. Aune, P. T. Reynolds, P. Moriarty, S. McArthur, Ralph Bird, S. Federici, J. P. Finley, J. H. Buckley, Sinéad M. Griffin, Matthias Beilicke, P. Majumdar, Lucy Fortson, N. Galante, M. J. Lang, R. A. Ong, A. Varlotta, M. Kertzman, A. S Madhavan, Markus Böttcher, A. Lamerato, Q. Feng, John L. Quinn, Gordon T. Richards, E. Roache, G. D. Şentürk, Gernot Maier, D. S. Hanna, T. C. Arlen, Wei Cui, C. Gusbar, P. Roustazadeh, G. Hughes, Vladimir Vassiliev, H. Prokoph, S. P. Wakely, R. Welsing, Matthew R. Orr, V. Bugaev, C. Skole, G. H. Gillanders, Daniel Gall, P. Kaaret, Y. Khassen, E. Collins-Hughes, A. Iii. Garson, G. Tešić, Amy Furniss, Henric Krawczynski, S. Vincent, D. B. Saxon, N. H. Park, J. Millis, K. Li, J. S. Perkins, Martin Pohl, J. Dumm, G. H. Sembroski, S. Archambault, Reshmi Mukherjee, A. Weinstein, A. D. Falcone, A. McCann, A. O'Faolain de Bhroithe, David Kieda, M. Theiling, I. Telezhinsky, Jamie Holder, David A. Williams, D. Staszak, K. Ragan, B. Zitzer, J. Grube, Manel Errando, and A. Popkow
Subjects: Smithsonian institution, Astrophysics::High Energy Astrophysical Phenomena, Cosmic background radiation, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, cosmic background radiation, timing explorer, Cosmic infrared background, gamma rays: galaxies, strong flares, Blazar, bl lacertae objects: general, Diffuse radiation, Physics, gamma-ray observations, bl lacertae objects: individual (1es1218+30.4), particle-acceleration, tev blazars, Astronomy, Institut für Physik und Astronomie, Astronomy and Astrophysics, Visible radiation, galaxies: jets, veritas observations, diffuse radiation, Red shift, large-area telescope, x-ray, Space and Planetary Science, active galactic nuclei, extragalactic magnetic-fields, ddc:520
Abstract: We present the results of a multi-wavelength campaign targeting the blazar 1ES 1218+30.4 with observations with the 1.3 m McGraw-Hill optical telescope, the Rossi X-ray Timing Explorer (RXTE), the Fermi Gamma-Ray Space Telescope, and the Very Energetic Radiation Imaging Telescope Array System (VERITAS). The RXTE and VERITAS observations were spread over a 13 day period and revealed clear evidence for flux variability, and a strong X-ray and gamma-ray flare on 2009 February 26 (MJD 54888). The campaign delivered a well-sampled broadband energy spectrum with simultaneous RXTE and VERITAS very high energy (VHE, > 100 GeV) observations, as well as contemporaneous optical and Fermi observations. The 1ES 1218+30.4 broadband energy spectrum-the first with simultaneous X-ray and VHE gamma-ray energy spectra-is of particular interest as the source is located at a high cosmological redshift for a VHE source (z = 0.182), leading to strong absorption of VHE gamma rays by photons from the optical/infrared extragalactic background light (EBL) via gamma VHE +gamma EBL -> e(+) e(-)pair-creation processes. We model the data with a one-zone synchrotron self-Compton (SSC) emission model and with the extragalactic absorption predicted by several recent EBL models. We find that the observations are consistent with the SSC scenario and all the EBL models considered in this work. We discuss observational and theoretical avenues to improve on the EBL constraints.
Published: 2014
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53. Observation of Markarian 421 in TeV gamma rays over a 14-year time span

Author: M. J. Lang, J. Tyler, J. H. Buckley, D. A. Carter-Lewis, E. Collins-Hughes, G. H. Gillanders, S. P. Wakely, Daniel Gall, L. Ciupik, N. Galante, E. Roache, A. N. Otte, H. Krawczynski, T. Reynolds, M. P. Connolly, D. S. Hanna, Ralph Bird, G. Finnegan, Geza Gyuk, K. Ragan, A. W. Smith, C. Duke, A. Pichel, G. H. Sembroski, Lucy Fortson, R. Welsing, Abraham D. Falcone, T. C. Arlen, V. Bugaev, Matthew R. Orr, J. P. Finley, Wei Cui, Y. Khassen, V. A. Acciari, T. Aune, T. C. Weekes, S. M. Bradbury, John Toner, A. C. Rovero, A. Cesarini, A. S. Madhavan, Wystan Benbow, Martin Pohl, John L. Quinn, P. Moriarty, R. A. Ong, K. G. Gibbs, J. Dumm, J. S. Perkins, S. J. Fegan, S. Federici, A. Weinstein, Stephanie Wissel, M. Schroedter, I. de la Calle Perez, A. Varlotta, A. Bouvier, P. Kaaret, J. E. Ward, David Kieda, M. Theiling, Sinéad M. Griffin, M. Kertzman, A. O'Faolain de Bhroithe, D. J. Fegan, T. J. N. Nelson, J. A. Gaidos, David A. Williams, I. Telezhinsky, T. B. Humensky, Julie McEnery, D. Horan, D. Petry, J. Grube, M. Vivier, and F. Krennrich
Subjects: multiwavelength observations, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Active galactic nucleus, Ciencias Físicas, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Flux, Astrophysics, telescope, timing explorer, 01 natural sciences, Spectral line, law.invention, purl.org/becyt/ford/1 [https], Telescope, law, blazar markarian-421, emission, 0103 physical sciences, crab-nebula, flare, AGN, Blazar, tev gamma rays, 010303 astronomy & astrophysics, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Markarian 421, 010308 nuclear & particles physics, markarian 421, Gamma ray, Astronomy, Institut für Physik und Astronomie, Astronomy and Astrophysics, purl.org/becyt/ford/1.3 [https], TeV gamma rays, Astronomía, Crab Nebula, correlated variability, active galactic nuclei, ddc:540, agn, Astrophysics - High Energy Astrophysical Phenomena, Markarian galaxies, CIENCIAS NATURALES Y EXACTAS, energy, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: The variability of the blazar Markarian 421 in TeV gamma rays over a 14-year time period has been explored with the Whipple 10 m telescope. It is shown that the dynamic range of its flux variations is large and similar to that in X-rays. A correlation between the X-ray and TeV energy bands is observed during some bright flares and when the complete data sets are binned on long timescales. The main database consists of 878.4 hours of observation with the Whipple telescope, spread over 783 nights. The peak energy response of the telescope was 400 GeV with 20% uncertainty. This is the largest database of any TeV-emitting active galactic nucleus (AGN) and hence was used to explore the variability profile of Markarian 421. The time-averaged flux from Markarian 421 over this period was 0.446$\pm$0.008 Crab flux units. The flux exceeded 10 Crab flux units on three separate occasions. For the 2000-2001 season the average flux reached 1.86 Crab units, while in the 1996-1997 season the average flux was only 0.23 Crab units., Comment: 29 pages, 15 figures. Accepted for publication in Astroparticle Physics
Published: 2014
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54. Fermi-LAT Observations of the Gamma-Ray Burst GRB 130427A

Author: P. A. Jenke, Brian L Winer, Soebur Razzaque, A. A. Moiseev, L. R. Cominsky, Igor V. Moskalenko, Melissa Gibby, Yoshiyuki Inoue, Justin D. Finke, Olaf Reimer, Katsuaki Asano, Robert D. Preece, F. Loparco, E. Moretti, André Schulz, Akira Okumura, George Younes, Matthew G. Baring, D. Byrne, William S. Paciesas, Chryssa Kouveliotou, C. Favuzzi, Judith Racusin, Melissa Pesce-Rollins, Charles A. Meegan, Robert R. Rando, T. Jogler, S. J. Fegan, Luca Baldini, J. G. Thayer, W. B. Focke, P. Spinelli, Sylvain Guiriec, Ryo Yamazaki, P. N. Bhat, Alex Drlica-Wagner, Shuze Zhu, A. von Kienlin, Vandiver Chaplin, Francesco Giordano, Anne M. Diekmann, M. E. Monzani, Jean Ballet, T. A. Porter, Hoi-Fung Yu, A. Franckowiak, J. Michael Burgess, G. Godfrey, W. N. Johnson, W. B. Atwood, Nicola Omodei, S. Rainò, Jeffrey D. Scargle, J. R. Cummings, J. S. Perkins, R. A. Cameron, Tsunefumi Mizuno, R. E. Hughes, Denis Bastieri, Misty Giles, Nicola Giglietto, Rodrigo Nemmen, Shaolin Xiong, Stefano Ciprini, D. Hadasch, S. Germani, K. S. Wood, T. Ohsugi, Eleonora Troja, Stefan Funk, Colleen A. Wilson-Hodge, P. Bruel, G. Chiaro, D. Horan, F. de Palma, A. C. Collazzi, Julie McEnery, V. Pelassa, A. J. van der Horst, Neil Gehrels, L. Di Venere, David Gruber, J. E. Grove, Yasushi Fukazawa, E. J. Siskind, Hiromitsu Takahashi, Valerie Connaughton, A. De Angelis, Adam Goldstein, M. Mayer, V. La Parola, D. J. Thompson, Carmelo Sgrò, G. Tosti, M. N. Lovellette, P. A. Caraveo, Persis S. Drell, M. Roth, Gudlaugur Johannesson, D. Kocevski, V. Vasileiou, Marco Ajello, J. B. Thayer, J. Lande, Jonathan Granot, S. Murgia, P. Fusco, E. Nuss, David Paneque, Sheila McBreen, M. Kuss, T. L. Usher, Francesco Longo, S. Buson, F. Piron, Giacomo Vianello, Masanori Ohno, Felix Ryde, W. H. Cleveland, Emanuele Bonamente, Charles D. Dermer, Magnus Axelsson, Alice K. Harding, I. A. Grenier, Markus Ackermann, Justin Vandenbroucke, Michael S. Briggs, Vahé Petrosian, Luca Latronico, Jürgen Knödlseder, Gloria Spandre, P. M. Saz Parkinson, Ronaldo Bellazzini, Johann Cohen-Tanugi, R. Desiante, T. Kawano, M. Tinivella, Elizabeth C. Ferrara, Guido Barbiellini, Stephen F. Foley, G. A. Caliandro, C. C. Cheung, M. Deklotz, Elisabetta Bissaldi, E. Hays, A. Morselli, F. Gargano, M. Orienti, V. Vitale, J. Bregeon, R. Claus, Alberto Sartori, Y. Hanabata, L. Tibaldo, G. Pivato, A. Reimer, M. Brigida, D. Tierney, M. N. Mazziotta, Eda Sonbas, Arne Rau, Giancarlo Cusumano, Claudia Cecchi, S. Larsson, Diego F. Torres, Gerard Fitzpatrick, S. Cutini, R. M. Kippen, James Chiang, M. Hayashida, Hiroyasu Tajima, Jan Conrad, R. Buehler, Peter F. Michelson, Marcello Giroletti, Eric Charles, Steven Ritz, A. Chekhtman, P. Lubrano, Keith Bechtol, M. Razzano, Filippo D'Ammando, Ackermann M, Ajello M, Asano K, Atwood WB, Axelsson M, Baldini L, Ballet J, Barbiellini G, Baring MG, Bastieri D, Bechtol K, Bellazzini R, Bissaldi E, Bonamente E, Bregeon J, Brigida M, Bruel P, Buehler R, Burgess JM, Buson S, Caliandro GA, Cameron RA, Caraveo PA, Cecchi C, Chaplin V, Charles E, Chekhtman A, Cheung CC, Chiang J, Chiaro G, Ciprini S, Claus R, Cleveland W, Cohen-Tanugi J, Collazzi A, Cominsky LR, Connaughton V, Conrad J, Cutini S, DAmmando F, de Angelis A, DeKlotz M, de Palma F, Dermer CD, Desiante R, Diekmann A, Di Venere L, Drell PS, Drlica-Wagner A, Favuzzi C, Fegan SJ, Ferrara EC, Finke J, Fitzpatrick G, Focke WB, Franckowiak A, Fukazawa Y, Funk S, Fusco P, Gargano F, Gehrels N, Germani S, Gibby M, Giglietto N, Giles M, Giordano F, Giroletti M, Godfrey G, Granot J, Grenier IA, Grove JE, Gruber D, Guiriec S, Hadasch D, Hanabata Y, Harding AK, Hayashida M, Hays E, Horan D, Hughes RE, Inoue Y, Jogler T, Johannesson G, Johnson WN, Kawano T, Knodlseder J, Kocevski D, Kuss M, Lande J, Larsson S, Latronico L, Longo F, Loparco F, Lovellette MN, Lubrano P, Mayer M, Mazziotta MN, McEnery JE, Michelson PF, Mizuno T, Moiseev AA, Monzani ME, Moretti E, Morselli A, Moskalenko IV, Murgia S, Nemmen R, Nuss E, Ohno M, Ohsugi T, Okumura A, Omodei N, Orienti M, Paneque D, Pelassa V, Perkins JS, Pesce-Rollins M, Petrosian V, Piron F, Pivato G, Porter TA, Racusin JL, Raino S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Ritz S, Roth M, Ryde F, Sartori A, Parkinson PMS, Scargle JD, Schulz A, Sgro C, Siskind EJ, Sonbas E, Spandre G, Spinelli P, Tajima H, Takahashi H, Thayer JG, Thayer JB, Thompson DJ, Tibaldo L, Tinivella M, Torres DF, Tosti G, Troja E, Usher TL, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Winer BL, Wood KS, Yamazaki R, Younes G, Yu HF, Zhu SJ, Bhat PN, Briggs MS, Byrne D, Foley S, Goldstein A, Jenke P, Kippen RM, Kouveliotou C, McBreen S, Meegan C, Paciesas WS, Preece R, Rau A, Tierney D, van der Horst AJ, von Kienlin A, Wilson-Hodge C, Xiong S, Cusumano G, La Parola V, Cummings JR, M., Ackermann, M., Ajello, K., Asano, W. B., Atwood, M., Axelsson, L., Baldini, J., Ballet, BARBIELLINI AMIDEI, Guido, M. G., Baring, D., Bastieri, K., Bechtol, R., Bellazzini, Bissaldi, Elisabetta, E., Bonamente, J., Bregeon, M., Brigida, P., Bruel, R., Buehler, J. M., Burge, S., Buson, G. A., Caliandro, R. A., Cameron, P. A., Caraveo, C., Cecchi, V., Chaplin, E., Charle, A., Chekhtman, C. C., Cheung, J., Chiang, G., Chiaro, S., Ciprini, R., Clau, W., Cleveland, J., Cohen Tanugi, A., Collazzi, L. R., Cominsky, V., Connaughton, J., Conrad, S., Cutini, F., D'Ammando, A. d., Angeli, M., Deklotz, F. d., Palma, C. D., Dermer, R., Desiante, A., Diekmann, L. D., Venere, P. S., Drell, A., Drlica Wagner, C., Favuzzi, S. J., Fegan, E. C., Ferrara, J., Finke, G., Fitzpatrick, W. B., Focke, A., Franckowiak, Y., Fukazawa, S., Funk, P., Fusco, F., Gargano, N., Gehrel, S., Germani, M., Gibby, N., Giglietto, M., Gile, F., Giordano, M., Giroletti, G., Godfrey, J., Granot, I. A., Grenier, J. E., Grove, D., Gruber, S., Guiriec, D., Hadasch, Y., Hanabata, A. K., Harding, M., Hayashida, E., Hay, D., Horan, R. E., Hughe, Y., Inoue, T., Jogler, G., Johannesson, W. N., Johnson, T., Kawano, J., Knoedlseder, D., Kocevski, M., Ku, J., Lande, S., Larsson, L., Latronico, Longo, Francesco, F., Loparco, M. N., Lovellette, P., Lubrano, M., Mayer, M. N., Mazziotta, J. E., Mcenery, P. F., Michelson, T., Mizuno, A. A., Moiseev, M. E., Monzani, E., Moretti, A., Morselli, I. V., Moskalenko, S., Murgia, R., Nemmen, E., Nu, M., Ohno, T., Ohsugi, A., Okumura, N., Omodei, M., Orienti, D., Paneque, V., Pelassa, J. S., Perkin, M., Pesce Rollin, V., Petrosian, F., Piron, G., Pivato, T. A., Porter, J. L., Racusin, S., Raino, R., Rando, M., Razzano, S., Razzaque, A., Reimer, O., Reimer, S., Ritz, M., Roth, F., Ryde, A., Sartori, P. M., Saz, J. D., Scargle, A., Schulz, C., Sgro, E. J., Siskind, E., Sonba, G., Spandre, P., Spinelli, H., Tajima, H., Takahashi, J. G., Thayer, J. B., Thayer, D. J., Thompson, L., Tibaldo, M., Tinivella, D. F., Torre, G., Tosti, E., Troja, T. L., Usher, J., Vandenbroucke, V., Vasileiou, G., Vianello, V., Vitale, B. L., Winer, K. S., Wood, R., Yamazaki, G., Youne, H. . ., F., S. J., Zhu, P. N., Bhat, M. S., Brigg, D., Byrne, S., Foley, A., Goldstein, P., Jenke, R. M., Kippen, C., Kouveliotou, S., Mcbreen, C., Meegan, W. S., Paciesa, R., Preece, A., Rau, D., Tierney, A. J., Van, A. v., Kienlin, C., Wilson Hodge, S., Xiong, G., Cusumano, V. L., Parola, J. R., Cummings, and High Energy Astrophys. & Astropart. Phys (API, FNWI)
Subjects: Astrophysics::High Energy Astrophysical Phenomena, SPECTRAL COMPONENT, Synchrotron radiation, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, LARGE-AREA TELESCOPE, HIGH-ENERGY EMISSION, AFTERGLOWS, PROMPT, law.invention, Telescope, Spitzer Space Telescope, law, Astrophysics::Galaxy Astrophysics, Physics, Multidisciplinary, Gamma ray, GRB 130427A, Astronomy, Afterglow, GRB, Fermi-LAT, ddc:500, Astrophysics - High Energy Astrophysical Phenomena, Gamma-ray burst, Fermi Gamma-ray Space Telescope
Abstract: The observations of the exceptionally bright gamma-ray burst (GRB) 130427A by the Large Area Telescope aboard the Fermi Gamma-ray Space Telescope provide constraints on the nature of such unique astrophysical sources. GRB 130427A had the largest fluence, highest-energy photon (95 GeV), longest $\gamma$-ray duration (20 hours), and one of the largest isotropic energy releases ever observed from a GRB. Temporal and spectral analyses of GRB 130427A challenge the widely accepted model that the non-thermal high-energy emission in the afterglow phase of GRBs is synchrotron emission radiated by electrons accelerated at an external shock., Comment: 30 pages, 6 figures. Accepted for publication in Science. Corresponding authors: S. Zhu (sjzhu@umd.edu); J. Chiang (jchiang@slac.stanford.edu); C. Dermer (charles.dermer@nrl.navy.mil); N. Omodei (nicola.omodei@stanford.edu); G. Vianello (giacomov@slac.stanford.edu); S. Xiong (Shaolin.Xiong@uah.edu)
Published: 2014
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55. A Three-Year Multi-Wavelength Study of the Very-High-Energy $\gamma$-Ray Blazar 1ES 0229+200

Author: F. Krennrich, A. McCann, A. Popkow, E. Aliu, M. Theiling, T. Aune, B. Zitzer, J. S. Perkins, J. H. Buckley, Wystan Benbow, V. V. Vassiliev, Manel Errando, A. O'Faolain de Bhroithe, A. Varlotta, K. Meagher, D. B. Kieda, P. Fortin, A. N. Otte, Anna Zajczyk, J. P. Dumm, Henrike Fleischhack, M. P. Connolly, John L. Quinn, Matthias Beilicke, S. Federici, Ralph Bird, P. Moriarty, Nicola Galante, J. Grube, I. Telezhinsky, Gernot Maier, J. P. Finley, B. Behera, Daniel Nieto, L. Ciupik, T. C. Weekes, Jamie Holder, Nahee Park, Xuhui Chen, K. L. Byrum, H. Prokoph, R. A. Ong, Y. Khassen, L. C. Reyes, S. McArthur, S. T. Griffiths, S. Archambault, Reshmi Mukherjee, J. Millis, S. P. Wakely, Wei Cui, V. Bugaev, D. Staszak, K. Ragan, A. W. Smith, D. S. Hanna, A. S Madhavan, C. Duke, Gordon T. Richards, T. C. Arlen, E. Roache, P. Kaaret, P. T. Reynolds, David A. Williams, R. Welsing, C. A. Johnson, Lucy Fortson, S. Vincent, Henric Krawczynski, A. J.R. Weinstein, M. J. Lang, Martin Pohl, G. H. Sembroski, A. D. Falcone, Q. Feng, T. B. Humensky, K. Berger, Matteo Cerruti, Amy Furniss, Sinéad M. Griffin, Gareth Hughes, M. Kertzman, A. Bouvier, Geza Gyuk, Pratik Majumdar, and G. H. Gillanders
Subjects: extragalactic background light, bl lacertae objects: individual (1es 0229+200, ver j0232+202), Active galactic nucleus, Astrophysics::High Energy Astrophysical Phenomena, galaxies: active, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, magnetic fields, 01 natural sciences, bl lacertae objects, 0103 physical sciences, intergalactic magnetic-field, Blazar, 010303 astronomy & astrophysics, bl lacertae objects: general, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, space-telescope, distant blazars, tev blazars, 010308 nuclear & particles physics, Institut für Physik und Astronomie, Astronomy and Astrophysics, gamma rays: general, diffuse radiation, large-area telescope, Crab Nebula, x-ray, Extragalactic background light, Space and Planetary Science, active galactic nuclei, Spectral energy distribution, Intergalactic travel, ddc:520, Astrophysics - High Energy Astrophysical Phenomena, lorentz factor, Fermi Gamma-ray Space Telescope, BL Lac object
Abstract: The high-frequency-peaked BL Lacertae object 1ES 0229+200 is a relatively distant (z = 0.1396), hard-spectrum (Gamma ~ 2.5), very-high-energy-emitting (E > 100 GeV) gamma-ray blazar. Very-high-energy measurements of this active galactic nucleus have been used to place constraints on the intensity of the extragalactic background light and the intergalactic magnetic field. A multi-wavelength study of this object centered around very-high-energy observations by VERITAS is presented. This study obtained, over a period of three years, an 11.7 standard deviation detection and an average integral flux F(E>300 GeV) = (23.3 +- 2.8_stat +- 5.8_sys) x 10^-9 photons m^-2 s^-1, or 1.7% of the Crab Nebula's flux (assuming the Crab Nebula spectrum measured by H.E.S.S). Supporting observations from Swift and RXTE are analyzed. The Swift observations are combined with previously published Fermi observations and the very-high-energy measurements to produce an overall spectral energy distribution which is then modeled assuming one-zone synchrotron-self-Compton emission. The chi^2 probability of the TeV flux being constant is 1.6%. This, when considered in combination with measured variability in the X-ray band, and the demonstrated variability of many TeV blazars, suggests that the use of blazars such as 1ES 0229+200 for intergalactic magnetic field studies may not be straightforward and challenges models that attribute hard TeV spectra to secondary gamma-ray production along the line of sight., Accepted for publication in ApJ
Published: 2014
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56. The environmental impact of livestock ranches in the Kalahari, Botswana: natural resource use, ecological change and human response in a dynamic dryland system

Author: David S.G. Thomas, J. S. Perkins, and Deborah Sporton
Subjects: education.field_of_study, Agroforestry, Natural resource economics, media_common.quotation_subject, Population, Soil Science, Subsistence agriculture, Development, Natural resource, Indigenous, Geography, Desertification, Land degradation, Environmental Chemistry, Environmental impact assessment, education, Environmental degradation, General Environmental Science, media_common
Abstract: This paper examines the ways in which a policy aiming to improve both use of an extensive dryland natural resource, and the well-being of rural peoples in Botswana, has impacted on the environment and upon indigenous land-use activities. The impacts of the Tribal Grazing Land Policy (TGLP) have been spatially and temporally variable. Previous assertions about its contribution to desertification may have been overstated, although environmental changes have certainly resulted from policy impacts. Effects upon traditional indigenous population coping strategies for environmental variability are considered both in terms of subsistence activities and the ability to respond to drought events. It is concluded that the policy has not met its environmental, pastoral production or societal objectives, largely because it was founded on unestablished assumptions. Large-scale environmental degradation and desertification, however, cannot yet be attributed to the TGLP, but it can be contended that the policy has reduced both environmental and societal resilience to natural environmental variability. Copyright © 2000 John Wiley & Sons, Ltd.
Published: 2000
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57. Discovery of TeV Gamma-ray Emission Toward Supernova Remnant SNR G78.2+2.1

Author: M. Kertzman, A. O'Faolain de Bhroithe, M. Schroedter, Vikram V. Dwarkadas, S. Vincent, Wei Cui, M. J. Lang, S. Thibadeau, A. N. Otte, M. P. Connolly, A. McCann, R. Mukherjee, D. B. Saxon, N. H. Park, J. Millis, T. Aune, J. E. Ward, A. Cesarini, P. Moriarty, John L. Quinn, T. B. Humensky, A. Furniss, Frank Krennrich, A. S. Madhavan, G. Tešić, Gernot Maier, H. Prokoph, A. Varlotta, Wystan Benbow, S. P. Wakely, Eric V. Gotthelf, E. Roache, J. P. Finley, S. Archambault, H. J. Rose, R. A. Ong, Ralph Bird, G. H. Sembroski, P. Kaaret, Amanda Weinstein, Abraham D. Falcone, R. Welsing, Vladimir Vassiliev, L. Ciupik, T. C. Weekes, J. Grube, D. Gall, Geza Gyuk, K. Tsurusaki, S. Federici, Manel Errando, T. C. Arlen, J. H. Buckley, G. H. Gillanders, P. Majumdar, T. J. N. Nelson, S. McArthur, N. Galante, S. Godambe, Dirk Pandel, S. Griffin, G. Finnegan, C. Skole, C. Duke, David A. Williams, N. Karlsson, G. D. Şentürk, T. Weisgarber, H. Huan, E. Aliu, I. Telezhinsky, K. Lee, Jamie Holder, A. Popkow, J. Tyler, A. Bouvier, D. S. Hanna, V. Bugaev, J. S. Perkins, Martin Pohl, Q. Feng, J. Dumm, P. T. Reynolds, David Kieda, M. Theiling, Lucy Fortson, Karen Byrum, S. M. Bradbury, A. Cannon, E. Collins-Hughes, H. Krawczynski, M. Beilicke, M. Orr, G. Hughes, K. Ragan, B. Zitzer, J. Ruppel, R. Dickherber, Y. Khassen, and Luis C. Reyes
Subjects: catalog, Astrophysics::High Energy Astrophysical Phenomena, Hadron, Flux, FOS: Physical sciences, Cosmic ray, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, cosmic rays, Observatory, 0103 physical sciences, origin, Supernova remnant, 010303 astronomy & astrophysics, 2cg078+2, Astrophysics::Galaxy Astrophysics, acceleration of particles, Physics, search, High Energy Astrophysical Phenomena (astro-ph.HE), particle-acceleration, 010308 nuclear & particles physics, hess, Gamma ray, Institut für Physik und Astronomie, counterpart, Astronomy and Astrophysics, gamma rays: general, Particle acceleration, Crab Nebula, Space and Planetary Science, ism: supernova remnants, ddc:520, High Energy Physics::Experiment, Astrophysics - High Energy Astrophysical Phenomena, fermi
Abstract: We report the discovery of an unidentified, extended source of very-high-energy (VHE) gamma-ray emission, VER J2019+407, within the radio shell of the supernova remnant SNR G78.2+2.1, using 21.4 hours of data taken by the VERITAS gamma-ray observatory in 2009. These data confirm the preliminary indications of gamma-ray emission previously seen in a two-year (2007-2009) blind survey of the Cygnus region by VERITAS. VER J2019+407, which is detected at a post-trials significance of 7.5 standard deviations in the 2009 data, is localized to the northwestern rim of the remnant in a region of enhanced radio and X-ray emission. It has an intrinsic extent of 0.23^{\circ} \pm 0.03^{\circ} (stat)+0.04^{\circ}_{-0.02}^{\circ}(sys) and its spectrum is well-characterized by a differential power law (dN/dE = N_0 \times (E/TeV)^{-\Gamma}) with a photon index of {\Gamma} = 2.37 \pm 0.14 (stat) \pm 0.20 (sys) and a flux normalization of N0 = 1.5 \pm 0.2 (stat) \pm 0.4(sys) \times 10^-12 ph TeV^{-1} cm^{-2} s^{-1}. This yields an integral flux of 5.2 \pm 0.8 (stat) \pm 1.4 (sys) \times 10^-12 ph cm^{-2} s^{-1} above 320 GeV, corresponding to 3.7% of the Crab Nebula flux. We consider the relationship of the TeV gamma-ray emission with the GeV gamma-ray emission seen from SNR G78.2+2.1 as well as that seen from a nearby cocoon of freshly accelerated cosmic rays. Multiple scenarios are considered as possible origins for the TeV gamma-ray emission, including hadronic particle acceleration at the supernova remnant shock., Comment: 18 pages, 5 figures, accepted for publication in ApJ
Published: 2013
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58. VERITAS Observations of the Microquasar Cygnus X-3

Author: A. Varlotta, Martin Pohl, J. S. Perkins, David Kieda, P. Moriarty, Nicola Galante, J. Grube, M. P. Connolly, David A. Williams, M. J. Lang, Xuhui Chen, Matthias Beilicke, Abraham D. Falcone, I. Telezhinsky, A. McCann, G. H. Sembroski, Daniel Nieto, Wei Cui, Q. Feng, A. O'Faolain de Bhroithe, G. H. Gillanders, Jamie Holder, Y. Khassen, H. Prokoph, Henric Krawczynski, A. J.R. Weinstein, D. S. Hanna, F. Sheidaei, K. Berger, Geza Gyuk, T. B. Humensky, L. C. Reyes, Karen Byrum, P. T. Reynolds, Pratik Majumdar, Sinéad M. Griffin, D. Staszak, K. Ragan, Matteo Cerruti, Gareth Hughes, M. Kertzman, B. Zitzer, Lucy Fortson, R. A. Ong, Amy Furniss, S. Vincent, A. W. Smith, A. S Madhavan, Ralph Bird, C. Duke, Gordon T. Richards, Manel Errando, E. Roache, S. Federici, S. T. Griffiths, Michael L. McCollough, A. Bouvier, P. Kaaret, Wystan Benbow, S. McArthur, S. Archambault, Reshmi Mukherjee, A. Popkow, A. N. Otte, V. Bugaev, John L. Quinn, N. H. Park, J. V. Tucci, Gernot Maier, J. P. Finley, S. P. Wakely, T. C. Weekes, D. Pandel, L. Ciupik, Jean-Francois Rajotte, J. Tyler, J. H. Buckley, J. P. Dumm, and M. Theiling
Subjects: Astrophysics::High Energy Astrophysical Phenomena, Radiation imaging, FOS: Physical sciences, Astrophysics, gamma rays: stars, 01 natural sciences, law.invention, Telescope, x-rays: individual (cygnus x-3), law, 0103 physical sciences, cyg x-3, 010303 astronomy & astrophysics, acceleration of particles, Physics, search, High Energy Astrophysical Phenomena (astro-ph.HE), binaries: close, 010308 nuclear & particles physics, Gamma ray, Institut für Physik und Astronomie, Astronomy and Astrophysics, gamma-ray emission, large-area telescope, scattering halo, x-ray, mission, Space and Planetary Science, cherenkov telescopes, ddc:520, relativistic jet, Astrophysics - High Energy Astrophysical Phenomena, constraints
Abstract: We report results from TeV gamma-ray observations of the microquasar Cygnus X-3. The observations were made with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) over a time period from 2007 June 11 to 2011 November 28. VERITAS is most sensitive to gamma rays at energies between 85 GeV to 30 TeV. The effective exposure time amounts to a total of about 44 hours, with the observations covering six distinct radio/X-ray states of the object. No significant TeV gamma-ray emission was detected in any of the states, nor with all observations combined. The lack of a positive signal, especially in the states where GeV gamma rays were detected, places constraints on TeV gamma-ray production in Cygnus X-3. We discuss the implications of the results., Comment: 23 pages, 4 figures, 3 tables, accepted for publication in ApJ
Published: 2013
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59. MULTIWAVELENGTH OBSERVATIONS OF THE TeV BINARY LS I +61° 303 WITH VERITAS, Fermi -LAT, AND Swift /XRT DURING A TeV OUTBURST

Author: S. Archambault, Gernot Maier, A. McCann, R. A. Ong, P. T. Reynolds, Lucy Fortson, N. Galante, S. P. Wakely, J. P. Finley, P. Fortin, A. D. Falcone, S. T. Griffiths, Y. Khassen, T. C. Weekes, A. W. Smith, Martin Pohl, Gordon T. Richards, Geza Gyuk, M. J. Lang, J. Dumm, M. Beilicke, S. Griffin, A. N. Otte, P. Majumdar, M. P. Connolly, K. Berger, L. Ciupik, B. Behera, D. Staszak, N. H. Park, Wystan Benbow, D. S. Hanna, John L. Quinn, G. H. Gillanders, Matteo Cerruti, E. Aliu, C. Skole, V. Bugaev, A. Varlotta, S. Federici, Q. Feng, A. Furniss, J. S. Perkins, David Kieda, G. Ratliff, S. Vincent, P. Kaaret, Gareth Hughes, E. Roache, R. Mukherjee, I. Telezhinsky, P. Moriarty, Jamie Holder, Ralph Bird, M. Kertzman, Xuhui Chen, J. Grube, A. O'Faolain de Bhroithe, A. Weinstein, A. Bouvier, Frank Krennrich, S. McArthur, F. Sheidaei, Wei Cui, H. Prokoph, T. B. Humensky, A. Popkow, Anna Zajczyk, J. Tyler, K. Ragan, B. Zitzer, Jean-Francois Rajotte, G. H. Sembroski, and R. Welsing
Subjects: Swift, Astrophysics::High Energy Astrophysical Phenomena, Binary number, FOS: Physical sciences, Astrophysics, telescope, gamma rays: stars, 01 natural sciences, law.invention, spectrum, Telescope, star, law, gamma-ray binary, 0103 physical sciences, emission, +61-degrees-303, 010303 astronomy & astrophysics, computer.programming_language, acceleration of particles, relativistic processes, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), 010308 nuclear & particles physics, Astronomy and Astrophysics, binaries: general, x-ray, Space and Planetary Science, x-rays: binaries, Spectral energy distribution, ddc:520, Satellite, High Energy Physics::Experiment, Astrophysics - High Energy Astrophysical Phenomena, computer, Fermi Gamma-ray Space Telescope
Abstract: We present the results of a multiwavelength observational campaign on the TeV binary system LS I +61 303 with the VERITAS telescope array (>200 GeV), Fermi-LAT (0.3-300 GeV), and Swift-XRT (2-10 keV). The data were taken from December 2011 through January 2012 and show a strong detection in all three wavebands. During this period VERITAS obtained 24.9 hours of quality selected livetime data in which LS I +61 303 was detected at a statistical sig- nificance of 11.9 sigma. These TeV observations show evidence for nightly variability in the TeV regime at a post-trial significance of 3.6 sigma. The combination of the simultaneously obtained TeV and X-ray fluxes do not demonstrate any evidence for a correlation between emission in the two bands. For the first time since the launch of the Fermi satellite in 2008, this TeV detection allows the construction of a detailed MeV-TeV spectral energy distribution from LS I +61 303. This spectrum shows a distinct cutoff in emission near 4 GeV, with emission seen by the VERITAS observations following a simple power-law above 200 GeV. This feature in the spectrum of LS I +61 303, obtained from overlapping observations with Fermi-LAT and VERITAS, may indicate that there are two distinct populations of accelerated particles producing the GeV and TeV emission., Accepted for Publication in ApJ
Published: 2013
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60. Determination of the Point-spread Function for the Fermi Large Area Telescope from On-orbit Data and Limits on Pair Halos of Active Galactic Nuclei

Author: G. Busetto, Brian L Winer, S. Cutini, A. A. Moiseev, Katsuaki Asano, Francesco Longo, Gudlaugur Johannesson, F. Loparco, E. Do Couto E Silva, W. Mitthumsiri, T. A. Porter, A. P. Waite, T. J. Brandt, Jean Ballet, Stefan Funk, Daniel Sánchez, Claudia Lavalley, Sho Nishino, Alex Drlica-Wagner, Justin Vandenbroucke, T. E. Stephens, A. Morselli, V. Vitale, Jeffrey D. Scargle, P. Fusco, Stefano Ciprini, Igor V. Moskalenko, Matthew Kerr, A. W. Borgland, I. A. Grenier, S. Germani, T. Ohsugi, Eleonora Troja, Miranda Jackson, Nicola Omodei, Guido Barbiellini, S. J. Fegan, Olaf Reimer, Zhenwei Yang, Elliott D. Bloom, G. Godfrey, Kent S. Wood, T. Jogler, Carmelo Sgrò, Riccardo Rando, Soebur Razzaque, Jay P. Norris, M. Razzano, P. Fortin, L. S. Rochester, C. Favuzzi, V. Vasileiou, R. Claus, Matthew Wood, Stephan Zimmer, J. F. Ormes, N. Gehrels, James Chiang, Hiroyasu Tajima, Gino Tosti, Jan Conrad, F. de Palma, R. E. Hughes, E. Wallace, Dario Gasparrini, Patrick Weltevrede, E. Nuss, Paola Grandi, P. Lubrano, Hiromitsu Takahashi, M. Brigida, Sylvain Chaty, A. Chekhtman, David Paneque, Claudia Cecchi, S. Rainò, J. G. Thayer, T. Kamae, Tsunefumi Mizuno, Randall P. Johnson, Rodrigo Nemmen, R. Dubois, E. Orlando, J. M. Casandjian, D. Horan, F. D'Ammando, W. B. Focke, M. Kuss, C. Monte, M. E. Monzani, Gloria Spandre, P. Spinelli, M. N. Mazziotta, Jun Kataoka, Pascal Bruel, J. Mehault, Emanuele Bonamente, R. Buehler, J. E. Grove, S. Larsson, T. L. Usher, Francesco Giordano, D. J. Thompson, Daniela Hadasch, M. Roth, Yasushi Fukazawa, T. H. Burnett, A. S. Johnson, M. Orienti, S. Murgia, O. Tibolla, Benoit Lott, Peter F. Michelson, Marcello Giroletti, Takaaki Tanaka, F. Piron, A. Snyder, Keith Bechtol, Johan Bregeon, Johann Cohen-Tanugi, Alice Allafort, Roberto Mignani, Eric Charles, Julie McEnery, Morihiro Hayashida, E. Hays, Steven Ritz, D. J. Suson, C. C. Cheung, W. McConville, L. C. Reyes, Marco Ajello, J. B. Thayer, M. Naumann-Godo, L. Tibaldo, W. B. Atwood, J. S. Perkins, Nicola Giglietto, F. Gargano, Luca Latronico, G. A. Caliandro, H. Poon, S. Colafrancesco, M. N. Lovellette, P. A. Caraveo, Persis S. Drell, M. Tinivella, Elizabeth C. Ferrara, V. Pelassa, E. J. Siskind, J. H. Panetta, Markus Ackermann, A. N. Cillis, R. A. Cameron, Luca Baldini, M. Pierbattista, Denis Bastieri, A. von Kienlin, C. Romoli, J. Lande, Sylvain Guiriec, A. Reimer, S. Buson, P. M. Saz Parkinson, Suk-Han Lee, Melissa Pesce-Rollins, T. Glanzman, Jürgen Knödlseder, G. Pivato, Eugenio Bottacini, Charles D. Dermer, X. Hou, Giacomo Vianello, Ronaldo Bellazzini, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), Istituto Nazionale di Fisica Nucleare, sezione di Bari (INFN, sezione di Bari), Istituto Nazionale di Fisica Nucleare (INFN), GLAST, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Particules de Montpellier (LUPM), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Ackermann, M., Ajello, M., Allafort, A., Asano, K., Atwood, W. B., Baldini, L., Ballet, J., BARBIELLINI AMIDEI, Guido, Bastieri, D., Bechtol, K., Bellazzini, R., Bloom, E. D., Bonamente, E., Borgland, A. W., Bottacini, E., Brandt, T. J., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Burnett, T. H., Busetto, G., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Charles, E., Chaty, S., Chekhtman, A., Cheung, C. C., Chiang, J., Cillis, A. N., Ciprini, S., Claus, R., Cohen Tanugi, J., Colafrancesco, S., Conrad, J., Cutini, S., D'Ammando, F., de Palma, F., Dermer, C. D., Silva, E. do Couto e., Drell, P. S., Drlica Wagner, A., Dubois, R., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Focke, W. B., Fortin, P., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grandi, P., Grenier, I. A., Grove, J. E., Guiriec, S., Hadasch, D., Hayashida, M., Hays, E., Horan, D., Hou, X., Hughes, R. E., Jackson, M. S., Jogler, T., Jóhannesson, G., Johnson, R. P., Johnson, A. S., Kamae, T., Kataoka, J., Kerr, M., Knödlseder, J., Kuss, M., Lande, J., Larsson, S., Latronico, L., Lavalley, C., Lee, S. H., Longo, Francesco, Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Mazziotta, M. N., Mcconville, W., Mcenery, J. E., Mehault, J., Michelson, P. F., Mignani, R. P., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Naumann Godo, M., Nemmen, R., Nishino, S., Norris, J. P., Nuss, E., Ohsugi, T., Omodei, N., Orienti, M., Orlando, E., Ormes, J. F., Paneque, D., Panetta, J. H., Pelassa, V., Perkins, J. S., Pesce Rollins, M., Pierbattista, M., Piron, F., Pivato, G., Poon, H., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Reyes, L. C., Ritz, S., Rochester, L. S., Romoli, C., Roth, M., Sanchez, D. A., Saz Parkinson, P. M., Scargle, J. D., Sgrò, C., Siskind, E. J., Snyder, A., Spandre, G., Spinelli, P., Stephens, T. E., Suson, D. J., Tajima, H., Takahashi, H., Tanaka, T., Thayer, J. G., Thayer, J. B., Thompson, D. J., Tibaldo, L., Tibolla, O., Tinivella, M., Tosti, G., Troja, E., Usher, T. L., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., von Kienlin, A., Waite, A. P., Wallace, E., Weltevrede, P., Winer, B. L., Wood, K. S., Wood, M., Yang, Z., Zimmer, S., Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Ackermann M, Ajello M, Allafort A, Asano K, Atwood WB, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Bloom ED, Bonamente E, Borgland AW, Bottacini E, Brandt TJ, Bregeon J, Brigida M, Bruel P, Buehler R, Burnett TH, Busetto G, Buson S, Caliandro GA, Cameron RA, Caraveo PA, Casandjian JM, Cecchi C, Charles E, Chaty S, Chekhtman A, Cheung CC, Chiang J, Cillis AN, Ciprini S, Claus R, Cohen-Tanugi J, Colafrancesco S, Conrad J, Cutini S, DAmmando F, de Palma F, Dermer CD, Silva EDE, Drell S, Drlica-Wagner A, Dubois R, Favuzzi C, Fegan SJ, Ferrara EC, Focke WB, Fortin P, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Gehrels N, Germani S, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Grandi P, Grenier IA, Grove JE, Guiriec S, Hadasch D, Hayashida M, Hays E, Horan D, Hou X, Hughes RE, Jackson MS, Jogler T, Johannesson G, Johnson RP, Johnson AS, Kamae T, Kataoka J, Kerr M, Knodlseder J, Kuss M, Lande J, Larsson S, Latronico L, Lavalley C, Lee SH, Longo F, Loparco F, Lott B, Lovellette MN, Lubrano P, Mazziotta MN, McConville W, McEnery JE, Mehault J, Michelson PF, Mignani RP, Mitthumsiri W, Mizuno T, Moiseev AA, Monte C, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Naumann-Godo M, Nemmen R, Nishino S, Norris JP, Nuss E, Ohsugi T, Omodei N, Orienti M, Orlando E, Ormes JF, Paneque D, Panetta JH, Pelassa V, Perkins JS, Pesce-Rollins M, Pierbattista M, Piron F, Pivato G, Poon H, Porter TA, Raino S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Reyes LC, Ritz S, Rochester LS, Romoli C, Roth M, Sanchez DA, Parkinson PMS, Scargle JD, Sgro C, Siskind EJ, Snyder A, Spandre G, Spinelli P, Stephens TE, Suson DJ, Tajima H, Takahashi H, Tanaka T, Thayer JG, Thayer JB, Thompson DJ, Tibaldo L, Tibolla O, Tinivella M, Tosti G, Troja E, Usher TL, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, von Kienlin A, Waite AP, Wallace E, Weltevrede P, Winer BL, Wood KS, Wood M, Yang Z, Zimmer S, National Institute for Nuclear Physics (INFN), and Université de Montpellier (UM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Ciencias Físicas, EXTRAGALACTIC MAGNETIC-FIELDS, halo [galaxies], galaxies: halos, Astrophysics, 01 natural sciences, galaxies, [gamma rays], law.invention, Spitzer Space Telescope, law, 1ES 0229+200, SPACE-TELESCOPE, 010303 astronomy & astrophysics, Physics, TEV BLAZARS, detector [instrumentation], [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astrophysics::Instrumentation and Methods for Astrophysics, detectors, intergalactic medium [instrumentation], VHE GAMMA-RAYS, galaxies: active – galaxies: halos – gamma rays: galaxies – instrumentation: detectors – intergalactic medium, halos [galaxies], active [galaxies], intergalactic medium, Astrophysics - High Energy Astrophysical Phenomena, CIENCIAS NATURALES Y EXACTAS, Point spread function, [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Active galactic nucleus, Astrophysics::High Energy Astrophysical Phenomena, galaxies: active, Astrophysics::Cosmology and Extragalactic Astrophysics, Telescope, 0103 physical sciences, gamma rays: galaxies, instrumentation: detectors, galaxie [gamma rays], Blazar, SOURCE CATALOG, Astrophysics::Galaxy Astrophysics, BACKGROUND LIGHT, 010308 nuclear & particles physics, Astronomy, CONSTRAINTS, Astronomy and Astrophysics, Quasar, PULSAR, Galaxy, DISCOVERY, Astronomía, Space and Planetary Science, ddc:520, Fermi Gamma-ray Space Telescope
Abstract: The astrophysical journal 765(1), 54 (2013). doi:10.1088/0004-637X/765/1/54, The Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope is a pair-conversion telescope designed to detect photons with energies from ≈20 MeV to >300 GeV. The pre-launch response functions of the LAT were determined through extensive Monte Carlo simulations and beam tests. The point-spread function (PSF) characterizing the angular distribution of reconstructed photons as a function of energy and geometry in the detector is determined here from two years of on-orbit data by examining the distributions of γ rays from pulsars and active galactic nuclei (AGNs). Above 3 GeV, the PSF is found to be broader than the pre-launch PSF. We checked for dependence of the PSF on the class of γ-ray source and observation epoch and found none. We also investigated several possible spatial models for pair-halo emission around BL Lac AGNs. We found no evidence for a component with spatial extension larger than the PSF and set upper limits on the amplitude of halo emission in stacked images of low- and high-redshift BL Lac AGNs and the TeV blazars 1ES0229+200 and 1ES0347–121, Published by Univ.11032, Chicago, Ill. [u.a.]
Published: 2013
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61. Long-term multiwavelength studies of high-redshift blazar 0836+710

Author: Kirill Sokolovsky, D. J. Thompson, Emmanouil Angelakis, Davide Donato, Stefan Larsson, J. A. Zensus, J. S. Perkins, Aysun Akyüz, Lars Fuhrmann, O. M. Kurtanidze, and Çukurova Üniversitesi
Subjects: High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Jet (fluid), galaxies [Gamma rays], Active galactic nucleus, active [Galaxies], Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astronomy and Astrophysics, individual: 0836+710 [Quasars], Galaxies: active, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, medicine.disease_cause, Power law, Redshift, Gamma rays: galaxies, Wavelength, Space and Planetary Science, medicine, Spectral energy distribution, Quasars: individual: 0836+710, Astrophysics - High Energy Astrophysical Phenomena, Blazar, Ultraviolet
Abstract: Aims. The observation of gamma -ray flares from blazar 0836+710 in 2011, following a period of quiescence, offered an opportunity to study correlated activity at different wavelengths for a high-redshift (z=2.218) active galactic nucleus. Methods. Optical and radio monitoring, plus Fermi-LAT gamma-ray monitoring provided 2008-2012 coverage, while Swift offered auxiliary optical, ultraviolet, and X-ray information. Other contemporaneous observations were used to construct a broad-band spectral energy distribution. Results. There is evidence of correlation but not a measurable lag between the optical and gamma-ray flaring emission. On the contrary, there is no clear correlation between radio and gamma-ray activity, indicating radio emission regions that are unrelated to the parts of the jet that produce the gamma-rays. The gamma-ray energy spectrum is unusual in showing a change of shape from a power law to a curved spectrum when going from the quiescent state to the active state., 11 pages, 10 figures, Accepted for publication in A&A
Published: 2013

62. HESS and Fermi-LAT discovery of gamma-rays from the blazar 1ES 1312-423

Author: J. Biteau, Michael Punch, G. Fontaine, Mateusz Janiak, S. J. Fegan, M. Weidinger, Svenja Carrigan, E. Birsin, Gilles Henri, André Schulz, Christian Farnier, G. Lamanna, D. Goering, Dieter Horns, Anna Zajczyk, P. Wagner, K. Dutson, A. Woernlein, Emmanuel Moulin, F. Stinzing, B. Giebels, Alexandre Marcowith, C. L. Naumann, A. A. Zdziarski, M. J. Vorster, A. Jacholkowska, P. Willmann, Michal Dyrda, Thomas Lohse, G. Puehlhofer, T. Garrigoux, Christo Venter, J. Brucker, Gavin Rowell, Dirk Lennarz, R. de los Reyes, Denis Wouters, V. Sahakian, Christoph Deil, Jamie Stevens, M. K. Daniel, Elisabetta Bissaldi, T. Kneiske, J. S. Perkins, S. Haeffner, C. Jahn, U. F. Katz, R. Moderski, A. Zech, Vincent Marandon, D. Klochkov, S. Schwarzburg, H. J. Voelk, P. Espigat, C. Stegmann, Nu. Komin, K. Stycz, F. Schuessler, Tanya Edwards, Luke O'c. Drury, Andreas Quirrenbach, C. Couturier, M. Gajdus, Guillaume Dubus, J. F. Glicenstein, K. Bernloehr, Catherine Boisson, Stefan Ohm, I. Oya, Jacek Niemiec, M. Kieffer, S. Pita, M. Holler, Michael Zacharias, M. Dalton, A. Cheesebrough, Pierre Brun, J. Perez, Philip G. Edwards, Olaf Reimer, S. Schwemmer, Jan Conrad, Matthias Kadler, N. Maxted, Manuel Meyer, J. Dyks, E. de Oña Wilhelmi, A. Reimer, Fabio Acero, Andrea Santangelo, Francois Brun, M. Chrétien, L. Rob, A. Fiasson, D. Fernandez, Matteo Cerruti, M. Panter, M. de Naurois, G. Maurin, Thomas Murach, U. Menzler, F. Krayzel, S. Klepser, Anna Barnacka, B. Khélifi, Roopesh Ojha, G. Hermann, M. A. Kastendieck, Regis Terrier, M. Tluczykont, G. Vasileiadis, M. V. Fernandes, M. Paz Arribas, Francesca Volpe, C. Trichard, M. Fuessling, Werner Hofmann, Michał Ostrowski, P. P. Krueger, F. Feinstein, G. Cologna, C. van Eldik, Jim Hinton, Andreas Hillert, J. D. Hague, M. C. Medina, Y. A. Gallant, H.-S. Zechlin, Felix Jankowsky, Peter Eger, Ullrich Schwanke, C-C Lu, A. Djannati-Ataï, L. Oakes, Henning Gast, M. Renaud, Martin Raue, A. G. Akhperjanian, O. Hervet, R. Steenkamp, I. D. Davids, Iurii Sushch, R. D. Parsons, S. Rosier-Lees, P. deWilt, K. Katarzyński, Marek Jamrozy, M. Mohamed, Helene Sol, J. Harris, Sabrina Casanova, Karl Kosack, Frank M. Rieger, J. Mehault, F. Spiess, S. Raab, A. Abramowski, J.-P. Tavernet, W. Kluzniak, T. J. L. McComb, P-O. Petrucci, B. Peyaud, R. White, S. Colafrancesco, I. Jung, B. Rudak, Kathrin Egberts, P. M. Chadwick, B. Degrange, Marianne Lemoine-Goumard, R. Chalme-Calvet, R. C. G. Chaves, Yvonne Becherini, Anna Szostek, Petter Hofverberg, Aion Viana, B. Opitz, A. Foerster, E. O. Anguener, D. Kolitzus, G. Heinzelmann, J. Bolmont, Guy Pelletier, Alicja Wierzcholska, S. Kaufmann, M. H. Grondin, Helen Poon, A. Lopatin, J.-P. Lenain, Reinhard Schlickeiser, Pol Bordas, Hugh Dickinson, J. Becker Tjus, Daniel Sánchez, M. Grudzińska, N. W. Pekeur, Tomasz Bulik, G. Spengler, S. J. Nolan, Joachim Hahn, W. Domainko, A. Balzer, Stefan Wagner, Gisela Anton, M. Mayer, Cameron B Rulten, S. Balenderan, Felix Aharonian, H. Laffon, K. Valerius, Julien Lefaucheur, D. Nedbal, L. Stawarz, P. Vincent, S. Krakau, Martin Ward, Laboratoire Univers et Particules de Montpellier (LUPM), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Montpellier 2 - Sciences et Techniques (UM2), AstroParticule et Cosmologie (APC (UMR_7164)), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), FERMI, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Annecy de Physique des Particules (LAPP), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), APC - Astrophysique des Hautes Energies (APC - AHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), HESS, Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Université de Montpellier (UM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), Laboratoire d'Annecy de Physique des Particules (LAPP/Laboratoire d'Annecy-le-Vieux de Physique des Particules), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Dipartimento di Astronomia, Universita degli Studi di Bologna, Università di Bologna [Bologna] (UNIBO)-Università di Bologna [Bologna] (UNIBO), 10103449 - Krüger, Petrus Paulus, 22050574 - Pekeur, Nicolette Whilna, 12006653 - Venter, Christo, 12792322 - Vorster, Michael Johannes, 24922986 - Sushch, Iurii, 23909196 - Casanova, Sabrina, A., Abramowski, F., Acero, F., Aharonian, A. G., Akhperjanian, E., Anguener, G., Anton, S., Balenderan, A., Balzer, A., Barnacka, Y., Becherini, J. B., Tju, K., Bernloehr, E., Birsin, Bissaldi, Elisabetta, J., Biteau, C., Boisson, J., Bolmont, P., Borda, J., Brucker, F., Brun, P., Brun, T., Bulik, S., Carrigan, S., Casanova, M., Cerruti, P. M., Chadwick, R., Chalme Calvet, R. C., G., A., Cheesebrough, M., Chretien, S., Colafrancesco, G., Cologna, J., Conrad, C., Couturier, M., Dalton, M. K., Daniel, I. D., David, B., Degrange, C., Deil, P., Dewilt, H. J., Dickinson, A., Djannati Atai, W., Domainko, L. O., '., G., Dubu, K., Dutson, J., Dyk, M., Dyrda, T., Edward, K., Egbert, P., Eger, P., Espigat, C., Farnier, S., Fegan, F., Feinstein, M. V., Fernande, D., Fernandez, A., Fiasson, G., Fontaine, A., Foerster, M., Fuessling, M., Gajdu, Y. A., Gallant, T., Garrigoux, H., Gast, B., Giebel, J. F., Glicenstein, D., Goering, M. . ., H., M., Grudzinska, S., Haeffner, J. D., Hague, J., Hahn, J., Harri, G., Heinzelmann, G., Henri, G., Hermann, O., Hervet, A., Hillert, J. A., Hinton, W., Hofmann, P., Hofverberg, M., Holler, D., Horn, A., Jacholkowska, C., Jahn, M., Jamrozy, M., Janiak, F., Jankowsky, I., Jung, M. A., Kastendieck, K., Katarzynski, U., Katz, S., Kaufmann, B., Khelifi, M., Kieffer, S., Klepser, D., Klochkov, W., Kluzniak, T., Kneiske, D., Kolitzu, N., Komin, K., Kosack, S., Krakau, F., Krayzel, P. P., Krueger, H., Laffon, G., Lamanna, J., Lefaucheur, M., Lemoine Goumard, J. . ., P., D., Lennarz, T., Lohse, A., Lopatin, C. . ., C., V., Marandon, A., Marcowith, G., Maurin, N., Maxted, M., Mayer, T. J., L., M. C., Medina, J., Mehault, U., Menzler, M., Meyer, R., Moderski, M., Mohamed, E., Moulin, T., Murach, C. L., Naumann, M. d., Nauroi, D., Nedbal, J., Niemiec, S. J., Nolan, L., Oake, S., Ohm, E. d., Ona, B., Opitz, M., Ostrowski, I., Oya, M., Panter, R. D., Parson, M. P., Arriba, N. W., Pekeur, G., Pelletier, J., Perez, P. . ., O., B., Peyaud, S., Pita, H., Poon, G., Puehlhofer, M., Punch, A., Quirrenbach, S., Raab, M., Raue, A., Reimer, O., Reimer, M., Renaud, R. d., Lo, F., Rieger, L., Rob, S., Rosier Lee, G., Rowell, B., Rudak, C. B., Rulten, V., Sahakian, D. A., Sanchez, A., Santangelo, R., Schlickeiser, F., Schuessler, A., Schulz, U., Schwanke, S., Schwarzburg, S., Schwemmer, H., Sol, G., Spengler, F., Spie, L., Stawarz, R., Steenkamp, C., Stegmann, F., Stinzing, K., Stycz, I., Sushch, A., Szostek, R., Terrier, M., Tluczykont, C., Trichard, K., Valeriu, C. v., Eldik, G., Vasileiadi, C., Venter, A., Viana, P., Vincent, H. J., Voelk, F., Volpe, M., Vorster, S. J., Wagner, P., Wagner, M., Ward, M., Weidinger, R., White, A., Wierzcholska, P., Willmann, A., Woernlein, D., Wouter, M., Zacharia, A., Zajczyk, A. A., Zdziarski, A., Zech, H. . ., S., J. S., Perkin, R., Ojha, J., Steven, P. G., Edward, and M., Kadler
Subjects: [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], gamma-rays: galaxies, Radio galaxy, BL Lacertae objects: individual: 1ES 1312-423, Astrophysics::High Energy Astrophysical Phenomena, Centaurus A, galaxies: active, jets [galaxies], FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 7. Clean energy, 01 natural sciences, radiation mechanisms: non-thermal, galaxies: jets, 0103 physical sciences, High Energy Stereoscopic System, Blazar, 010303 astronomy & astrophysics, individual: 1ES 1312-423 [BL Lacertae objects], Astrophysics::Galaxy Astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Spectral index, 010308 nuclear & particles physics, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astronomy, Institut für Physik und Astronomie, Astronomy and Astrophysics, non-thermal [radiation mechanisms], Crab Nebula, galaxies [gamma-rays], jet [galaxies], 13. Climate action, Space and Planetary Science, individual: 1ES 1312–423 [BL Lacertae objects], active [galaxies], ddc:520, Spectral energy distribution, High Energy Physics::Experiment, Astrophysics - High Energy Astrophysical Phenomena, Bl Lacertae objects: individual: 1ES 1312-423, Galaxies: active, Galaxies: jets, Gamma-rays: galaxies, Radiation mechanisms: non-thermal, Fermi Gamma-ray Space Telescope
Abstract: A deep observation campaign carried out by the High Energy Stereoscopic System (H.E.S.S.) on Centaurus A enabled the discovery of gamma rays from the blazar 1ES 1312-423, two degrees away from the radio galaxy. With a differential flux at 1 TeV of (1.9 +/-0.6(stat) +/-0.4(sys)) x 10^{-13} /cm^2 /s /TeV corresponding to 0.5% of the Crab nebula differential flux and a spectral index of 2.9 +/- 0.5 (stat) +/- 0.2 (sys), 1ES 1312-423 is one of the faintest sources ever detected in the very high energy (E>100 GeV) extragalactic sky. A careful analysis using three and a half years of Fermi-LAT data allows the discovery at high energies (E>100 MeV) of a hard spectrum (index of 1.4 +/- 0.4 (stat) +/- 0.2 (sys)) source coincident with 1ES 1312-423. Radio, optical, UV and X-ray observations complete the spectral energy distribution of this blazar, now covering 16 decades in energy. The emission is successfully fitted with a synchrotron self Compton model for the non-thermal component, combined with a black-body spectrum for the optical emission from the host galaxy., 12 pages, 10 figures, accepted in MNRAS
Published: 2013
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63. Constraints on the Galactic Population of TeV Pulsar Wind Nebulae Using Fermi Large Area Telescope Observations

Author: Janet Conrad, A. Reimer, Xian Hou, M. Tinivella, A. S. Johnson, Elizabeth C. Ferrara, A. Morselli, R. Claus, Marianne Lemoine-Goumard, M. Brigida, Hiromitsu Takahashi, Frederic Piron, V. Vasileiou, Emanuele Bonamente, Kent S. Wood, S. Murgia, C. Cecchi, Dario Gasparrini, M. Orienti, T. Reposeur, Y. Takeuchi, Denis Bastieri, E. Do Couto E Silva, F. Giordano, T. A. Porter, J.H. Panetta, Alice K. Harding, Alex Drlica-Wagner, Melissa Pesce-Rollins, T. J. Brandt, R. C. G. Chaves, W. B. Focke, T. Jogler, John W. Hewitt, L. Falletti, Sylvain Guiriec, A. Chekhtman, E. D. Bloom, Akira Okumura, M. E. Monzani, J. S. Perkins, Nicola Giglietto, Jean Ballet, Markus Ackermann, Tsunefumi Mizuno, V. Vitale, Michael Mayer, Gudlaugur Johannesson, S. J. Fegan, M. N. Lovellette, Stefano Ciprini, J. B. Thayer, E. J. Siskind, Yoshiyuki Inoue, G. Chiaro, P. A. Caraveo, Persis S. Drell, Gino Tosti, Justin Vandenbroucke, R. E. Hughes, Guido Barbiellini, Takeshi Nakamori, T. Grégoire, Luca Baldini, G. Godfrey, Martino Marelli, F. Gargano, T. Ohsugi, J. E. Grove, Yasushi Fukazawa, Francesco Longo, T. Glanzman, Gloria Spandre, M.-H. Grondin, D. J. Thompson, Eleonora Troja, Miranda Jackson, Alice Allafort, M. N. Mazziotta, J. Chiang, F. de Palma, Morihiro Hayashida, J. G. Thayer, Yasunobu Uchiyama, M. Kuss, P. Fusco, Matthew Kerr, L. Di Venere, Giacomo Vianello, Jürgen Knödlseder, Y. Hanabata, Johann Cohen-Tanugi, G. Pivato, T. Kawano, R. Rousseau, C. Favuzzi, G. A. Caliandro, Eugenio Bottacini, Z. Yang, Eric Nuss, J. Lande, Charles D. Dermer, A. Franckowiak, A. B. Hill, Stefan Funk, Michael Werner, Eric Charles, E. Hays, Steven Ritz, D. J. Suson, Carmelo Sgrò, Riccardo Rando, Ronaldo Bellazzini, David Paneque, S. Rainò, Francesco Massaro, J. F. Ormes, S. Cutini, F. Loparco, W. Mitthumsiri, I. A. Grenier, David A. Smith, S. Buson, Fabio Acero, P. Lubrano, C. Monte, R. A. Cameron, Roger Blandford, L. Latronico, Rodrigo Nemmen, Kazuhiko Hayashi, Diego F. Torres, Elena Orlando, D. Horan, J. Mehault, Johan Bregeon, B. L. Winer, Julie McEnery, M. Roth, Marco Ajello, L. Tibaldo, D. Hadasch, Igor V. Moskalenko, Olaf Reimer, Pascal Bruel, Omar Tibolla, R. Buehler, A. Schulz, Peter F. Michelson, Marcello Giroletti, P. Spinelli, Keith Bechtol, Stefan Larsson, M. Razzano, P. M. Saz Parkinson, Filippo D'Ammando, T. Kamae, M. Dalton, Laboratoire Univers et Particules de Montpellier (LUPM), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Istituto Nazionale di Fisica Nucleare, sezione di Bari (INFN, sezione di Bari), Istituto Nazionale di Fisica Nucleare (INFN), FERMI, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Acero F, Ackermann M, Ajello M, Allafort A, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bechtol K, Bellazzini R, Blandford RD, Bloom ED, Bonamente E, Bottacini E, Brandt TJ, Bregeon J, Brigida M, Bruel P, Buehler R, Buson S, Caliandro GA, Cameron RA, Caraveo PA, Cecchi C, Charles E, Chaves RCG, Chekhtman A, Chiang J, Chiaro G, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, Dalton M, DAmmando F, de Palma F, Dermer CD, Di Venere L, Silva EDE, Drell PS, Drlica-Wagner A, Falletti L, Favuzzi C, Fegan SJ, Ferrara EC, Focke WB, Franckowiak A, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Gregoire T, Grenier IA, Grondin MH, Grove JE, Guiriec S, Hadasch D, Hanabata Y, Harding AK, Hayashida M, Hayashi K, Hays E, Hewitt J, Hill AB, Horan D, Hou X, Hughes RE, Inoue Y, Jackson MS, Jogler T, Johannesson G, Johnson AS, Kamae T, Kawano T, Kerr M, Knodlseder J, Kuss M, Lande J, Larsson S, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lovellette MN, Lubrano P, Marelli M, Massaro F, Mayer M, Mazziotta MN, McEnery JE, Mehault J, Michelson PF, Mitthumsiri W, Mizuno T, Monte C, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Nakamori T, Nemmen R, Nuss E, Ohsugi T, Okumura A, Orienti M, Orlando E, Ormes JF, Paneque D, Panetta JH, Perkins JS, Pesce-Rollins M, Piron F, Pivato G, Porter TA, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Reposeur T, Ritz S, Roth M, Rousseau R, Parkinson PMS, Schulz A, Sgro C, Siskind EJ, Smith DA, Spandre G, Spinelli P, Suson DJ, Takahashi H, Takeuchi Y, Thayer JG, Thayer JB, Thompson DJ, Tibaldo L, Tibolla O, Tinivella M, Torres DF, Tosti G, Troja E, Uchiyama Y, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Werner M, Winer BL, Wood KS, Yang Z, Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Acero, F., Ackermann, M., Ajello, M., Allafort, A., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Blandford, R. D., Bloom, E. D., Bonamente, E., Bottacini, E., Brandt, T. J., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Cecchi, C., Charles, E., Chaves, R. C. G., Chekhtman, A., Chiang, J., Chiaro, G., Ciprini, S., Claus, R., Cohen Tanugi, J., Conrad, J., Cutini, S., Dalton, M., D'Ammando, F., de Palma, F., Dermer, C. D., Di Venere, L., Silva, E. do Couto e., Drell, P. S., Drlica Wagner, A., Falletti, L., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Focke, W. B., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grégoire, T., Grenier, I. A., Grondin, M. H., Grove, J. E., Guiriec, S., Hadasch, D., Hanabata, Y., Harding, A. K., Hayashida, M., Hayashi, K., Hays, E., Hewitt, J., Hill, A. B., Horan, D., Hou, X., Hughes, R. E., Inoue, Y., Jackson, M. S., Jogler, T., Jóhannesson, G., Johnson, A. S., Kamae, T., Kawano, T., Kerr, M., Knödlseder, J., Kuss, M., Lande, J., Larsson, S., Latronico, L., Lemoine Goumard, M., Longo, Francesco, Loparco, F., Lovellette, M. N., Lubrano, P., Marelli, M., Massaro, F., Mayer, M., Mazziotta, M. N., Mcenery, J. E., Mehault, J., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nakamori, T., Nemmen, R., Nuss, E., Ohsugi, T., Okumura, A., Orienti, M., Orlando, E., Ormes, J. F., Paneque, D., Panetta, J. H., Perkins, J. S., Pesce Rollins, M., Piron, F., Pivato, G., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Reimer, A., Reimer, O., Reposeur, T., Ritz, S., Roth, M., Rousseau, R., Saz Parkinson, P. M., Schulz, A., Sgrò, C., Siskind, E. J., Smith, D. A., Spandre, G., Spinelli, P., Suson, D. J., Takahashi, H., Takeuchi, Y., Thayer, J. G., Thayer, J. B., Thompson, D. J., Tibaldo, L., Tibolla, O., Tinivella, M., Torres, D. F., Tosti, G., Troja, E., Uchiyama, Y., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Werner, M., Winer, B. L., Wood, K. S., Yang, Z., Université de Montpellier (UM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), National Institute for Nuclear Physics (INFN), and Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Montpellier 2 - Sciences et Techniques (UM2)
Subjects: [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astrophysics::High Energy Astrophysical Phenomena, Population, FOS: Physical sciences, Context (language use), Astrophysics, 01 natural sciences, law.invention, Telescope, Pulsar, law, 0103 physical sciences, Radiative transfer, Astrophysics::Solar and Stellar Astrophysics, education, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), education.field_of_study, 010308 nuclear & particles physics, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astrophysics::Instrumentation and Methods for Astrophysics, Spectral density, Astronomy and Astrophysics, gamma rays: general, Galactic plane, Space and Planetary Science, ddc:520, Physics::Accelerator Physics, Astrophysics - High Energy Astrophysical Phenomena, general [gamma rays], Fermi Gamma-ray Space Telescope
Abstract: Pulsar wind nebulae (PWNe) have been established as the most populous class of TeV gamma-ray emitters. Since launch, the Fermi Large Area Telescope (LAT)identified five high-energy (100MeV, Comment: 72 pages, 13 figures
Published: 2013
Full Text: View/download PDF

64. MULTIWAVELENGTH OBSERVATIONS OF GRB 110731A: GeV EMISSION FROM ONSET TO AFTERGLOW

Author: T. Ohsugi, Akihiko Fukui, W. S. Paciesas, P. Fusco, Eleonora Troja, G. Godfrey, Miranda Jackson, Dario Gasparrini, Marco Ajello, J. B. Thayer, S. Rainò, Tsunefumi Mizuno, S. Murgia, J. E. Grove, Yasushi Fukazawa, Luca Latronico, I. A. Grenier, O. Littlejohns, Matthew G. Baring, Daniel Sánchez, Peter Mészáros, L. Tibaldo, Jonathan Granot, A. De Angelis, R. M. Kippen, Judith Racusin, V. Vasileiou, Elisabetta Bissaldi, R. Filgas, S. Buson, M. Tinivella, F. de Palma, G. Tosti, F. Piron, Stefano Ciprini, Sheila McBreen, P. Bruel, Jan Conrad, C. Monte, T. Jogler, Nicola Omodei, Masanori Ohno, A. P. Waite, Hiromitsu Takahashi, Melissa Pesce-Rollins, Valerie Connaughton, Giacomo Vianello, T. L. Usher, J. G. Thayer, Takashi Sako, Luca Baldini, Eda Sonbas, Alex Drlica-Wagner, E. Orlando, A. Reimer, K. S. Wood, Jürgen Knödlseder, M. Roth, J. Mehault, D. Kocevski, S. McGlynn, A. S. Johnson, S. Cutini, V. Pelassa, E. J. Siskind, A. von Kienlin, David Gruber, Johan Bregeon, T. Glanzman, J. M. Burgess, P. N. Bhat, M. Naumann-Godo, Ronaldo Bellazzini, R. Buehler, C. Romoli, E. Hays, J. S. Perkins, S. J. Fegan, Igor V. Moskalenko, Julie McEnery, Brian L Winer, Nicola Giglietto, Katsuaki Asano, M. E. Monzani, Peter F. Michelson, Marcello Giroletti, Markus Ackermann, T. Nymark, Y. Hanabata, G. Pivato, Olaf Reimer, M. N. Lovellette, M. Hayashida, Robert D. Preece, P. A. Caraveo, A. Franckowiak, R. E. Hughes, Persis S. Drell, Charles D. Dermer, E. Do Couto E Silva, Eugenio Bottacini, Denis Bastieri, E. Moretti, F. D'Ammando, F. Loparco, C. Favuzzi, T. Krühler, W. Mitthumsiri, A. J. van der Horst, R. Claus, J. Lande, Sylvain Guiriec, F. Gargano, Johann Cohen-Tanugi, Zhenwei Yang, Daniela Hadasch, Michael S. Briggs, Carmelo Sgrò, Riccardo Rando, Francesco Longo, E. Nuss, David Paneque, M. Kuss, T. N. Ukwatta, Jay P. Norris, G. A. Caliandro, R. C. G. Chaves, James Chiang, Roger Blandford, M. Razzano, Soebur Razzaque, S. R. Oates, N. Gehrels, Suzanne Foley, Arne Rau, Gudlaugur Johannesson, Claudia Cecchi, Felix Ryde, M. Stamatikos, Justin Vandenbroucke, Guido Barbiellini, M. Orienti, A. Morselli, V. Vitale, A. Chekhtman, M. N. Mazziotta, M. Brigida, W. B. Focke, P. Spinelli, Chryssa Kouveliotou, S. Larsson, Francesco Giordano, R. A. Cameron, Jochen Greiner, S. Klose, Emanuele Bonamente, A. W. Borgland, Takaaki Tanaka, Paul J. Tristram, P. Lubrano, D. A. Kann, Eric Charles, Ackermann M, Ajello M, Asano K, Baldini L, Barbiellini G, Baring MG, Bastieri D, Bellazzini R, Blandford RD, Bonamente E, Borgland AW, Bottacini E, Bregeon J, Brigida M, Bruel P, Buehler R, Buson S, Caliandro GA, Cameron RA, Caraveo PA, Cecchi C, Charles E, Chaves RCG, Chekhtman A, Chiang J, Ciprini S, Claus R, Cohen-Tanugi J, Conrad J, Cutini S, DAmmando F, de Angelis A, de Palma F, Dermer CD, Silva EDE, Drell PS, Drlica-Wagner A, Favuzzi C, Fegan SJ, Focke WB, Franckowiak A, Fukazawa Y, Fusco P, Gargano F, Gasparrini D, Gehrels N, Giglietto N, Giordano F, Giroletti M, Glanzman T, Godfrey G, Granot J, Greiner J, Grenier IA, Grove JE, Guiriec S, Hadasch D, Hanabata Y, Hayashida M, Hays E, Hughes RE, Jackson MS, Jogler T, Johannesson G, Johnson AS, Knodlseder J, Kocevski D, Kuss M, Lande J, Larsson S, Latronico L, Longo F, Loparco F, Lovellette MN, Lubrano P, Mazziotta MN, McEnery JE, Mehault J, Meszaros P, Michelson PF, Mitthumsiri W, Mizuno T, Monte C, Monzani ME, Moretti E, Morselli A, Moskalenko IV, Murgia S, Naumann-Godo M, Norris JP, Nuss E, Nymark T, Ohno M, Ohsugi T, Omodei N, Orienti M, Orlando E, Paneque D, Perkins JS, Pesce-Rollins M, Piron F, Pivato G, Racusin JL, Raino S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Romoli C, Roth M, Ryde F, Sanchez DA, Sgro C, Siskind EJ, Sonbas E, Spinelli P, Stamatikos M, Takahashi H, Tanaka T, Thayer JG, Thayer JB, Tibaldo L, Tinivella M, Tosti G, Troja E, Usher TL, Vandenbroucke J, Vasileiou V, Vianello G, Vitale V, Waite AP, Winer BL, Wood KS, Yang Z, Gruber D, Bhat PN, Bissaldi E, Briggs MS, Burgess JM, Connaughton V, Foley S, Kippen RM, Kouveliotou C, McBreen S, McGlynn S, Paciesas WS, Pelassa V, Preece R, Rau A, van der Horst AJ, von Kienlin A, Kann DA, Filgas R, Klose S, Kruhler T, Fukui A, Sako T, Tristram PJ, Oates SR, Ukwatta TN, Littlejohns O, High Energy Astrophys. & Astropart. Phys (API, FNWI), Ackermann, M., Ajello, M., Asano, K., Baldini, L., BARBIELLINI AMIDEI, Guido, Baring, M. G., Bastieri, D., Bellazzini, R., Blandford, R. D., Bonamente, E., Borgland, A. W., Bottacini, E., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Cecchi, C., Charles, E., Chaves, R. C. G., Chekhtman, A., Chiang, J., Ciprini, S., Claus, R., Cohen Tanugi, J., Conrad, J., Cutini, S., D'Ammando, F., de Angelis, A., de Palma, F., Dermer, C. D., Silva, E. do Couto e., Drell, P. S., Drlica Wagner, A., Favuzzi, C., Fegan, S. J., Focke, W. B., Franckowiak, A., Fukazawa, Y., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Granot, J., Greiner, J., Grenier, I. A., Grove, J. E., Guiriec, S., Hadasch, D., Hanabata, Y., Hayashida, M., Hays, E., Hughes, R. E., Jackson, M. S., Jogler, T., Jóhannesson, G., Johnson, A. S., Knödlseder, J., Kocevski, D., Kuss, M., Lande, J., Larsson, S., Latronico, L., Longo, Francesco, Loparco, F., Lovellette, M. N., Lubrano, P., Mazziotta, M. N., Mcenery, J. E., Mehault, J., Mészáros, P., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Monte, C., Monzani, M. E., Moretti, E., Morselli, A., Moskalenko, I. V., Murgia, S., Naumann Godo, M., Norris, J. P., Nuss, E., Nymark, T., Ohno, M., Ohsugi, T., Omodei, N., Orienti, M., Orlando, E., Paneque, D., Perkins, J. S., Pesce Rollins, M., Piron, F., Pivato, G., Racusin, J. L., Rainò, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Romoli, C., Roth, M., Ryde, F., Sanchez, D. A., Sgrò, C., Siskind, E. J., Sonbas, E., Spinelli, P., Stamatikos, M., Takahashi, H., Tanaka, T., Thayer, J. G., Thayer, J. B., Tibaldo, L., Tinivella, M., Tosti, G., Troja, E., Usher, T. L., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Waite, A. P., Winer, B. L., Wood, K. S., Yang, Z., Gruber, D., Bhat, P. N., Bissaldi, Elisabetta, Briggs, M. S., Burgess, J. M., Connaughton, V., Foley, S., Kippen, R. M., Kouveliotou, C., Mcbreen, S., Mcglynn, S., Paciesas, W. S., Pelassa, V., Preece, R., Rau, A., van der Horst, A. J., von Kienlin, A., Kann, D. A., Filgas, R., Klose, S., Krühler, T., Fukui, A., Sako, T., Tristram, P. J., Oates, S. R., Ukwatta, T. N., and Littlejohns, O.
Subjects: Physics, Opacity, Astrophysics::High Energy Astrophysical Phenomena, Astronomy, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, individual (GRB110731A) [gamma-ray burst], Light curve, gamma-ray burst: individual (GRB110731A), Afterglow, law.invention, Telescope, Lorentz factor, symbols.namesake, Space and Planetary Science, law, Observatory, symbols, ddc:520, Astrophysics - High Energy Astrophysical Phenomena, Gamma-ray burst, Astrophysics::Galaxy Astrophysics, Fermi Gamma-ray Space Telescope
Abstract: The astrophysical journal 763(2), 71 (2013). doi:10.1088/0004-637X/763/2/71, We report on the multiwavelength observations of the bright, long gamma-ray burst GRB 110731A, by the Fermi and Swift observatories, and by the MOA and GROND optical telescopes. The analysis of the prompt phase reveals that GRB 110731A shares many features with bright Large Area Telescope bursts observed by Fermi during the first three years on-orbit: a light curve with short time variability across the whole energy range during the prompt phase, delayed onset of the emission above 100 MeV, extra power-law component and temporally extended high-energy emission. In addition, this is the first GRB for which simultaneous GeV, X-ray, and optical data are available over multiple epochs beginning just after the trigger time and extending for more than 800 s, allowing temporal and spectral analysis in different epochs that favor emission from the forward shock in a wind-type medium. The observed temporally extended GeV emission is most likely part of the high-energy end of the afterglow emission. Both the single-zone pair transparency constraint for the prompt signal and the spectral and temporal analysis of the forward-shock afterglow emission independently lead to an estimate of the bulk Lorentz factor of the jet Γ ~ 500-550., Published by Univ.11032, Chicago, Ill. [u.a.]
Published: 2013
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65. The Second Fermi Large Area Telescope Catalog of Gamma-ray Pulsars

Author: G. Busetto, Brian L Winer, John J. Ruan, A. A. Moiseev, Eric Charles, Steven Ritz, D. J. Suson, Luca Baldini, Simon Johnston, F. Loparco, N. Renault, W. Mitthumsiri, Na Wang, Sylvain Guiriec, I. A. Grenier, James Chiang, Jeffrey D. Scargle, Roger W. Romani, Jürgen Knödlseder, S. Germani, K. S. Wood, P. Lubrano, M. Marelli, Jayashree Roy, R. Buehler, Jun Kataoka, Gloria Spandre, Ronaldo Bellazzini, A. S. Johnson, S. Cutini, Michael Kramer, T. Ohsugi, Eleonora Troja, Miranda Jackson, Maura McLaughlin, T. Reposeur, Peter F. Michelson, Marcello Giroletti, Francesco Longo, R. C. G. Chaves, Yasunobu Uchiyama, Johann Cohen-Tanugi, M. Orienti, Alex Drlica-Wagner, Dario Gasparrini, M. Hayashida, Sylvain Chaty, Nanda Rea, E. D. Bloom, Jean Ballet, A. Morselli, Xian Hou, V. Vitale, T. Jogler, Charles D. Dermer, R. N. Manchester, D. Parent, M. E. Monzani, Andrea Belfiore, Stefano Ciprini, Bhaswati Bhattacharyya, Gemma H. Janssen, R. Rousseau, J. Lande, Scott M. Ransom, Michael Keith, Luca Latronico, P. R. den Hartog, Gino Tosti, M. Mayer, Francesco Massaro, R. E. Hughes, A. W. Chen, A. B. Hill, L. R. Cominsky, Igor V. Moskalenko, Melissa Pesce-Rollins, J. G. Thayer, M. Burgay, Elisabetta Bissaldi, Olaf Reimer, Paul S. Ray, Holger J. Pletsch, M. Tinivella, T. L. Usher, M. E. DeCesar, Jason W. T. Hessels, Paulo C. C. Freire, G. A. Caliandro, Jan Conrad, Elizabeth C. Ferrara, Takeshi Nakamori, J. M. Casandjian, Terri Brandt, Hiromitsu Takahashi, André Schulz, Patrick Weltevrede, Andrew W. Strong, M. N. Mazziotta, D. Dumora, C. Favuzzi, J. Mehault, Christo Venter, A. De Angelis, P. Fusco, L. Guillemot, D. J. Thompson, T. H. Burnett, Diego F. Torres, A. A. Abdo, E. Orlando, Gregory Desvignes, W. N. Johnson, Gilles Theureau, L. Tibaldo, S. Murgia, M. T. Wolff, C. Cecchi, Alberto Sartori, T. Glanzman, F. Piron, Rodrigo Nemmen, Matthew Kerr, Matthew G. Baring, D. Horan, Giacomo Vianello, Fernando Camilo, L. Di Venere, Gudlaugur Johannesson, O. Tibolla, Masanori Ohno, D. L. Wood, E. Hays, Y. Hanabata, G. Pivato, M. Roth, F. Gargano, Alice K. Harding, Ismaël Cognard, Benjamin Stappers, Justin Vandenbroucke, Emanuele Bonamente, J. F. Ormes, Eugenio Bottacini, T. A. Porter, Guido Barbiellini, E. J. Siskind, David A. Smith, L. Falletti, Denis Bastieri, R. Claus, Marianne Lemoine-Goumard, Johan Bregeon, D. Hadasch, Ryan Shannon, A. Possenti, A. Reimer, J. H. Panetta, M. Razzano, S. Rainò, Eric V. Gotthelf, Tsunefumi Mizuno, Filippo D'Ammando, Julie McEnery, T. Kamae, M. Brigida, Stephen E. Thorsett, R. P. Johnson, G. Chiaro, J. E. Grove, P. M. Saz Parkinson, J. S. Perkins, Paolo Giommi, Marco Ajello, J. B. Thayer, S. Larsson, S. Buson, Nicola Giglietto, A. De Luca, M. N. Lovellette, P. A. Caraveo, Persis S. Drell, Alice Allafort, Roberto Mignani, Tyrel J. Johnson, R. A. Cameron, A. Chekhtman, R. Dubois, W. B. Focke, P. Spinelli, Seth Digel, Francesco Giordano, John W. Hewitt, P. Bruel, V. Vasileiou, Matthew Wood, G. Godfrey, F. de Palma, Andrew Lyne, M.-H. Grondin, Robert R. Rando, M. Pierbattista, Cristobal M. Espinoza, Omer Celik, A. Franckowiak, Stefan Funk, Zhenwei Yang, Carmelo Sgrò, E. Nuss, David Paneque, M. Kuss, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Unité Scientifique de la Station de Nançay (USN), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), FERMI, Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Istituto Nazionale di Fisica Nucleare, sezione di Bari (INFN, sezione di Bari), National Institute for Nuclear Physics (INFN), IEEC-CSIC, Universitat Autònoma de Barcelona [Barcelona] (UAB), Laboratoire d'Astrophysique de Grenoble (LAOG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Particules de Montpellier (LUPM), Université de Montpellier (UM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Fermi-LAT, High Energy Astrophys. & Astropart. Phys (API, FNWI), Abdo AA, Ajello M, Allafort A, Baldini L, Ballet J, Barbiellini G, Baring MG, Bastieri D, Belfiore A, Bellazzini R, Bhattacharyya B, Bissaldi E, Bloom ED, Bonamente E, Bottacini E, Brandt TJ, Bregeon J, Brigida M, Bruel P, Buehler R, Burgay M, Burnett TH, Busetto G, Buson S, Caliandro GA, Cameron RA, Camilo F, Caraveo PA, Casandjian JM, Cecchi C, Celik O, Charles E, Chaty S, Chaves RCG, Chekhtman A, Chen AW, Chiang J, Chiaro G, Ciprini S, Claus R, Cognard I, Cohen-Tanugi J, Cominsky LR, Conrad J, Cutini S, DAmmando F, De Angelis A, DeCesar ME, De Luca A, Den Hartog PR, De Palma F, Dermer CD, Desvignes G, Digel SW, Di Venere L, Drell PS, Drlica-Wagner A, Dubois R, Dumora D, Espinoza CM, Falletti L, Favuzzi C, Ferrara EC, Focke WB, Franckowiak A, Freire PCC, Funk S, Fusco P, Gargano F, Gasparrini D, Germani S, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Gotthelf EV, Grenier IA, Grondin MH, Grove JE, Guillemot L, Guiriec S, Hadasch D, Hanabata Y, Harding AK, Hayashida M, Hays E, Hessels J, Hewitt J, Hill AB, Horan D, Hou X, Hughes RE, Jackson MS, Janssen GH, Jogler T, Johannesson G, Johnson RP, Johnson AS, Johnson TJ, Johnson WN, Johnston S, Kamae T, Kataoka J, Keith M, Kerr M, Knodlseder J, Kramer M, Kuss M, Lande J, Larsson S, Latronico L, Lemoine-Goumard M, Longo F, Loparco F, Lovellette MN, Lubrano P, Lyne AG, Manchester RN, Marelli M, Massaro F, Mayer M, Mazziotta MN, McEnery JE, McLaughlin MA, Mehault J, Michelson PF, Mignani RP, Mitthumsiri W, Mizuno T, Moiseev AA, Monzani ME, Morselli A, Moskalenko IV, Murgia S, Nakamori T, Nemmen R, Nuss E, Ohno M, Ohsugi T, Orienti M, Orlando E, Ormes JF, Paneque D, Panetta JH, Parent D, Perkins JS, Pesce-Rollins M, Pierbattista M, Piron F, Pivato G, Pletsch HJ, Porter TA, Possenti A, Raino S, Rando R, Ransom SM, Ray PS, Razzano M, Rea N, Reimer A, Reimer O, Renault N, Reposeur T, Ritz S, Romani RW, Roth M, Rousseau R, Roy J, Ruan J, Sartori A, Parkinson PMS, Scargle JD, Schulz A, Sgro C, Shannon R, Siskind EJ, Smith DA, Spandre G, Spinelli P, Stappers BW, Strong AW, Suson DJ, Takahashi H, Thayer JG, Thayer JB, Theureau G, Thompson DJ, Thorsett SE, Tibaldo L, Tibolla O, Tinivella M, Torres DF, Tosti G, Troja E, Uchiyama Y, Usher TL, Vandenbroucke J, Vasileiou V, Venter C, Vianello G, Vitale V, Wang N, Weltevrede P, Winer BL, Wolff MT, Wood DL, Wood KS, Wood M, Yang Z, Abdo, A. A., Ajello, M., Allafort, A., Baldini, L., Ballet, J., BARBIELLINI AMIDEI, Guido, Baring, M. G., Bastieri, D., Belfiore, A., Bellazzini, R., Bhattacharyya, B., Bissaldi, Elisabetta, Bloom, E. D., Bonamente, E., Bottacini, E., Brandt, T. J., Bregeon, J., Brigida, M., Bruel, P., Buehle, R., Burgay, M., Burnett, T. H., Busetto, G., Buson, S., Caliandro, G. A., Cameron, R. A., Camilo, F., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Çelik, Ö., Charles, E., Chaty, S., Chaves, R. C. G., Chekhtman, A., Chen, A. W., Chiang, J., Chiaro, G., Ciprini, S., Claus, R., Cognard, I., Cohen Tanugi, J., Cominsky, L. R., Conrad, J., Cutini, S., D'Ammando, F., de Angelis, A., Decesar, M. E., De Luca, A., den Hartog, P. R., de Palma, F., Dermer, C. D., Desvignes, G., Digel, S. W., Di Venere, L., Drell, P. S., Drlica Wagner, A., Dubois, R., Dumora, D., Espinoza, C. M., Falletti, L., Favuzzi, C., Ferrara, E. C., Focke, W. B., Franckowiak, A., Freire, P. C. C., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Germani, S., Giglietto, N., Giommi, P., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Gotthelf, E. V., Grenier, I. A., Grondin, M. H., Grove, J. E., Guillemot, L., Guiriec, S., Hadasch, D., Hanabata, Y., Harding, A. K., Hayashida, M., Hays, E., Hessels, J., Hewitt, J., Hill, A. B., Horan, D., Hou, X., Hughes, R. E., Jackson, M. S., Janssen, G. H., Jogler, T., Jóhannesson, G., Johnson, R. P., Johnson, A. S., Johnson, T. J., Johnson, W. N., Johnston, S., Kamae, T., Kataoka, J., Keith, M., Kerr, M., Knödlseder, J., Kramer, M., Kuss, M., Lande, J., Larsson, S., Latronico, L., Lemoine Goumard, M., Longo, Francesco, Loparco, F., Lovellette, M. N., Lubrano, P., Lyne, A. G., Manchester, R. N., Marelli, M., Massaro, F., Mayer, M., Mazziotta, M. N., Mcenery, J. E., Mclaughlin, M. A., Mehault, J., Michelson, P. F., Mignani, R. P., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nakamori, T., Nemmen, R., Nuss, E., Ohno, M., Ohsugi, T., Orienti, M., Orlando, E., Ormes, J. F., Paneque, D., Panetta, J. H., Parent, D., Perkins, J. S., Pesce Rollins, M., Pierbattista, M., Piron, F., Pivato, G., Pletsch, H. J., Porter, T. A., Possenti, A., Rainò, S., Rando, R., Ransom, S. M., Ray, P. S., Razzano, M., Rea, N., Reimer, A., Reimer, O., Renault, N., Reposeur, T., Ritz, S., Romani, R. W., Roth, M., Rousseau, R., Roy, J., Ruan, J., Sartori, A., Saz Parkinson, P. M., Scargle, J. D., Schulz, A., Sgrò, C., Shannon, R., Siskind, E. J., Smith, D. A., Spandre, G., Spinelli, P., Stappers, B. W., Strong, A. W., Suson, D. J., Takahashi, H., Thayer, J. G., Thayer, J. B., Theureau, G., Thompson, D. J., Thorsett, S. E., Tibaldo, L., Tibolla, O., Tinivella, M., Torres, D. F., Tosti, G., Troja, E., Uchiyama, Y., Usher, T. L., Vandenbroucke, J., Vasileiou, V., Venter, C., Vianello, G., Vitale, V., Wang, N., Weltevrede, P., Winer, B. L., Wolff, M. T., Wood, D. L., Wood, K. S., Wood, M., and Yang, Z.
Subjects: Catalogs pulsars, general stars, neutron, catalog, CRAB PULSAR, Astrophysics, 01 natural sciences, Pulsar wind nebula, general [pulsars], law.invention, neutron, Millisecond pulsar, law, catalogs, pulsars: general, stars: neutron, 010303 astronomy & astrophysics, general stars, Physics, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Astrophysics::Instrumentation and Methods for Astrophysics, WIND NEBULA, SUPERNOVA REMNANT G21.5-0.9, Astrophysics - High Energy Astrophysical Phenomena, PHOTON IMAGING CAMERA, [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], WHITE-DWARF COMPANION, MIDDLE-AGED PULSAR, DEEP OPTICAL OBSERVATIONS, NANCAY RADIO TELESCOPE, MILLISECOND PULSARS, LIGHT CURVES, Astrophysics::High Energy Astrophysical Phenomena, Catalogs pulsars, Astrophysics::Cosmology and Extragalactic Astrophysics, catalogs , pulsars: general , stars: neutron, Telescope, neutron [stars], Pulsar, 0103 physical sciences, Astrophysics::Galaxy Astrophysics, 010308 nuclear & particles physics, Crab Pulsar, catalogs – pulsars: general – stars: neutron, Astronomy, Astronomy and Astrophysics, Neutron star, Space and Planetary Science, ddc:520, X-ray pulsar, Fermi Gamma-ray Space Telescope
Abstract: This catalog summarizes 117 high-confidence > 0.1 GeV gamma-ray pulsar detections using three years of data acquired by the Large Area Telescope (LAT) on the Fermi satellite. Half are neutron stars discovered using LAT data, through periodicity searches in gamma-ray and radio data around LAT unassociated source positions. The 117 pulsars are evenly divided into three groups: millisecond pulsars, young radio-loud pulsars, and young radio-quiet pulsars. We characterize the pulse profiles and energy spectra and derive luminosities when distance information exists. Spectral analysis of the off-peak phase intervals indicates probable pulsar wind nebula emission for four pulsars, and off-peak magnetospheric emission for several young and millisecond pulsars. We compare the gamma-ray properties with those in the radio, optical, and X-ray bands. We provide flux limits for pulsars with no observed gamma-ray emission, highlighting a small number of gamma-faint, radio-loud pulsars. The large, varied gamma-ray pulsar sample constrains emission models. Fermi's selection biases complement those of radio surveys, enhancing comparisons with predicted population distributions., Comment: 145 pages. Online files at http://fermi.gsfc.nasa.gov/ssc/data/access/lat/2nd_PSR_catalog/ A typo in the value of the photon flux for CTA 1 (PSR J0007+7303) has been corrected in Table 9. NASA ADS at http://cdsads.u-strasbg.fr/abs/2013ApJS..208...17A
Published: 2013
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66. Discovery of TeV Gamma-ray Emission from CTA 1 by VERITAS

Author: A. N. Otte, G. H. Sembroski, M. P. Connolly, E. Aliu, T. J. N. Nelson, R. Welsing, K. Lee, L. Ciupik, M. Theiling, P. Moriarty, Eric V. Gotthelf, Geza Gyuk, N. Karlsson, J. P. Finley, Wei Cui, Q. Feng, Gernot Maier, T. C. Weekes, I. Telezhinsky, Jamie Holder, S. Thibadeau, D. Gall, Oleg Kargaltsev, A. O'Faolain de Bhroithe, H. Krawczynski, A. Furniss, N. Galante, S. P. Wakely, R. Mukherjee, R. A. Ong, E. Roache, R. Dickherber, H. Prokoph, S. Vincent, A. S. Madhavan, Wystan Benbow, Abraham D. Falcone, S. Griffin, G. Finnegan, A. W. Smith, Mallory S. E. Roberts, S. McArthur, C. Duke, B. Zitzer, P. T. Reynolds, P. Kaaret, K. Ragan, J. Tyler, F. Krennrich, Y. Khassen, M. Schroedter, A. Bouvier, Vikram V. Dwarkadas, M. Vivier, J. Grube, M. Beilicke, Manel Errando, D. Staszak, S. Federici, J. H. Buckley, P. Majumdar, J. S. Perkins, David Kieda, D. B. Saxon, E. Collins-Hughes, Luis C. Reyes, N. H. Park, David A. Williams, Patrick Slane, M. Orr, T. B. Humensky, T. Aune, S. Godambe, G. Hughes, T. Arlen, Lucy Fortson, A. Cesarini, John L. Quinn, Martin Pohl, J. Dumm, Vladimir Vassiliev, A. Varlotta, M. J. Lang, A. Weinstein, K. Tsurusaki, G. H. Gillanders, D. S. Hanna, G. Tešić, V. Bugaev, S. Archambault, and A. McCann
Subjects: catalog, gamma-rays: stars, Photon, Astrophysics::High Energy Astrophysical Phenomena, supernova remnant cta-1, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Pulsar wind nebula, atmospheric cherenkov telescopes, Pulsar, Observatory, hess j1825-137, evolution, 0103 physical sciences, pulsations, crab-nebula, Supernova remnant, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Spectral index, pulsars: individual (psr j0007+7303), 010308 nuclear & particles physics, Gamma ray, Astronomy and Astrophysics, x-rays: individual (rx j0007.0+7303), astronomy, supernovae: individual (g119.5+10.2), x-ray, Space and Planetary Science, ddc:520, High Energy Physics::Experiment, Astrophysics - High Energy Astrophysical Phenomena, pulsar-wind nebulae, Fermi Gamma-ray Space Telescope
Abstract: We report the discovery of TeV gamma-ray emission coincident with the shell-type radio supernova remnant (SNR) CTA 1 using the VERITAS gamma-ray observatory. The source, VER J0006+729, was detected as a 6.5 standard deviation excess over background and shows an extended morphology, approximated by a two-dimensional Gaussian of semi-major (semi-minor) axis 0.30 degree (0.24 degree) and a centroid 5' from the Fermi gamma-ray pulsar PSR J0007+7303 and its X-ray pulsar wind nebula (PWN). The photon spectrum is well described by a power-law dN/dE = N_0 (E/3 TeV)^(-\Gamma), with a differential spectral index of \Gamma = 2.2 +- 0.2_stat +- 0.3_sys, and normalization N_0 = (9.1 +- 1.3_stat +- 1.7_sys) x 10^(-14) cm^(-2) s^(-1) TeV^(-1). The integral flux, F_\gamma = 4.0 x 10^(-12) erg cm^(-2) s^(-1) above 1 TeV, corresponds to 0.2% of the pulsar spin-down power at 1.4 kpc. The energetics, co-location with the SNR, and the relatively small extent of the TeV emission strongly argue for the PWN origin of the TeV photons. We consider the origin of the TeV emission in CTA 1., Comment: 10 pages, 9 figures, accepted for publication in ApJ
Published: 2012
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67. THE FIRST FERMI LAT SUPERNOVA REMNANT CATALOG

Author: F. Acero, M. Ackermann, M. Ajello, L. Baldini, J. Ballet, G. Barbiellini, D. Bastieri, R. Bellazzini, E. Bissaldi, R. D. Blandford, E. D. Bloom, R. Bonino, E. Bottacini, T. J. Brandt, J. Bregeon, P. Bruel, R. Buehler, S. Buson, G. A. Caliandro, R. A. Cameron, R. Caputo, M. Caragiulo, P. A. Caraveo, J. M. Casandjian, E. Cavazzuti, C. Cecchi, A. Chekhtman, J. Chiang, G. Chiaro, S. Ciprini, R. Claus, J. M. Cohen, J. Cohen-Tanugi, L. R. Cominsky, B. Condon, J. Conrad, S. Cutini, F. D’Ammando, A. de Angelis, F. de Palma, R. Desiante, S. W. Digel, L. Di Venere, P. S. Drell, A. Drlica-Wagner, C. Favuzzi, E. C. Ferrara, A. Franckowiak, Y. Fukazawa, S. Funk, P. Fusco, F. Gargano, D. Gasparrini, N. Giglietto, P. Giommi, F. Giordano, M. Giroletti, T. Glanzman, G. Godfrey, G. A. Gomez-Vargas, I. A. Grenier, M.-H. Grondin, L. Guillemot, S. Guiriec, M. Gustafsson, D. Hadasch, A. K. Harding, M. Hayashida, E. Hays, J. W. Hewitt, A. B. Hill, D. Horan, X. Hou, G. Iafrate, T. Jogler, G. Jóhannesson, A. S. Johnson, T. Kamae, H. Katagiri, J. Kataoka, J. Katsuta, M. Kerr, J. Knödlseder, D. Kocevski, M. Kuss, H. Laffon, J. Lande, S. Larsson, L. Latronico, M. Lemoine-Goumard, J. Li, L. Li, F. Longo, F. Loparco, M. N. Lovellette, P. Lubrano, J. Magill, S. Maldera, M. Marelli, M. Mayer, M. N. Mazziotta, P. F. Michelson, W. Mitthumsiri, T. Mizuno, A. A. Moiseev, M. E. Monzani, E. Moretti, A. Morselli, I. V. Moskalenko, S. Murgia, R. Nemmen, E. Nuss, T. Ohsugi, N. Omodei, M. Orienti, E. Orlando, J. F. Ormes, D. Paneque, J. S. Perkins, M. Pesce-Rollins, V. Petrosian, F. Piron, G. Pivato, T. A. Porter, S. Rainò, R. Rando, M. Razzano, S. Razzaque, A. Reimer, O. Reimer, M. Renaud, T. Reposeur, R. Rousseau, P. M. Saz Parkinson, J. Schmid, A. Schulz, C. Sgrò, E. J. Siskind, F. Spada, G. Spandre, P. Spinelli, A. W. Strong, D. J. Suson, H. Tajima, H. Takahashi, T. Tanaka, J. B. Thayer, D. J. Thompson, L. Tibaldo, O. Tibolla, D. F. Torres, G. Tosti, E. Troja, Y. Uchiyama, G. Vianello, B. Wells, K. S. Wood, M. Wood, M. Yassine, P. R. den Hartog, S. Zimmer, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Laboratoire Univers et Particules de Montpellier (LUPM), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Montpellier 2 - Sciences et Techniques (UM2), Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Université de Montpellier (UM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Acero F, Ackermann M, Ajello M, Baldini L, Ballet J, Barbiellini G, Bastieri D, Bellazzini R, Bissaldi E, Blandford RD, Bloom ED, Bonino R, Bottacini E, Brandt TJ, Bregeon J, Bruel P, Buehler R, Buson S, Caliandro GA, Cameron RA, Caputo R, Caragiulo M, Caraveo PA, Casandjian JM, Cavazzuti E, Cecchi C, Chekhtman A, Chiang J, Chiaro G, Ciprini S, Claus R, Cohen JM, Cohen-Tanugi J, Cominsky LR, Condon B, Conrad J, Cutini S, DAmmando F, de Angelis A, de Palma F, Desiante R, Digel SW, Di Venere L, Drell PS, Drlica-Wagner A, Favuzzi C, Ferrara EC, Franckowiak A, Fukazawa Y, Funk S, Fusco P, Gargano F, Gasparrini D, Giglietto N, Giommi P, Giordano F, Giroletti M, Glanzman T, Godfrey G, Gomez-Vargas GA, Grenier IA, Grondin MH, Guillemot L, Guiriec S, Gustafsson M, Hadasch D, Harding AK, Hayashida M, Hays E, Hewitt JW, Hill AB, Horan D, Hou X, Iafrate G, Jogler T, Johannesson G, Johnson AS, Kamae T, Katagiri H, Kataoka J, Katsuta J, Kerr M, Knodlseder J, Kocevski D, Kuss M, Laffon H, Lande J, Larsson S, Latronico L, Lemoine-Goumard M, Li J, Li L, Longo F, Loparco F, Lovellette MN, Lubrano P, Magill J, Maldera S, Marelli M, Mayer M, Mazziotta MN, Michelson PF, Mitthumsiri W, Mizuno T, Moiseev AA, Monzani ME, Moretti E, Morselli A, Moskalenko IV, Murgia S, Nemmen R, Nuss E, Ohsugi T, Omodei N, Orienti M, Orlando E, Ormes JF, Paneque D, Perkins JS, Pesce-Rollins M, Petrosian V, Piron F, Pivato G, Porter TA, Raino S, Rando R, Razzano M, Razzaque S, Reimer A, Reimer O, Renaud M, Reposeur T, Rousseau R, Parkinson PMS, Schmid J, Schulz A, Sgro C, Siskind EJ, Spada F, Spandre G, Spinelli P, Strong AW, Suson DJ, Tajima H, Takahashi H, Tanaka T, Thayer JB, Thompson DJ, Tibaldo L, Tibolla O, Torres DF, Tosti G, Troja E, Uchiyama Y, Vianello G, Wells B, Wood KS, Wood M, Yassine M, den Hartog PR, Zimmer S, ITA, Acero, F., Ackermann, M., Ajello, M., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bellazzini, R., Bissaldi, E., Blandford, R. D., Bloom, E. D., Bonino, R., Bottacini, E., Brandt, T. J., Bregeon, J., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caputo, R., Caragiulo, M., Caraveo, P. A., Casandjian, J. M., Cavazzuti, E., Cecchi, C., Chekhtman, A., Chiang, J., Chiaro, G., Ciprini, S., Claus, R., Cohen, J. M., Cohen Tanugi, J., Cominsky, L. R., Condon, B., Conrad, J., Cutini, S., D'Ammando, F., Angelis, A. De, Palma, F. De, Desiante, R., Digel, S. W., Venere, L. Di, Drell, P. S., Drlica Wagner, A., Favuzzi, C., Ferrara, E. C., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Giglietto, N., Giommi, P., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Gomez Vargas, G. A., Grenier, I. A., Grondin, M. H., Guillemot, L., Guiriec, S., Gustafsson, M., Hadasch, D., Harding, A. K., Hayashida, M., Hays, E., Hewitt, J. W., Hill, A. B., Horan, D., Hou, X., Iafrate, G., Jogler, T., Jóhannesson, G., Johnson, A. S., Kamae, T., Katagiri, H., Kataoka, J., Katsuta, J., Kerr, M., Knödlseder, J., Kocevski, D., Kuss, M., Laffon, H., Lande, J., Larsson, S., Latronico, L., Lemoine Goumard, M., Li, J., Li, L., Longo, Francesco, Loparco, F., Lovellette, M. N., Lubrano, P., Magill, J., Maldera, S., Marelli, M., Mayer, M., Mazziotta, M. N., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monzani, M. E., Moretti, E., Morselli, A., Moskalenko, I. V., Murgia, S., Nemmen, R., Nuss, E., Ohsugi, T., Omodei, N., Orienti, M., Orlando, E., Ormes, J. F., Paneque, D., Perkins, J. S., Pesce Rollins, M., Petrosian, V., Piron, F., Pivato, G., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Renaud, M., Reposeur, T., Rousseau, R., Parkinson, P. M. Saz, Schmid, J., Schulz, A., Sgrò, C., Siskind, E. J., Spada, F., Spandre, G., Spinelli, P., Strong, A. W., Suson, D. J., Tajima, H., Takahashi, H., Tanaka, T., Thayer, J. B., Thompson, D. J., Tibaldo, L., Tibolla, O., Torres, D. F., Tosti, G., Troja, E., Uchiyama, Y., Vianello, G., Wells, B., Wood, K. S., Wood, M., Yassine, M., Den Hartog, P. R., and Zimmer, S.
Subjects: catalog, Acceleration of particles, Supernova Remnants, Astrophysics::High Energy Astrophysical Phenomena, Flux, Context (language use), Cosmic ray, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, 7. Clean energy, 01 natural sciences, law.invention, Telescope, law, 0103 physical sciences, Supernova remnant, ISM [gamma-rays], Cosmic rays, 010303 astronomy & astrophysics, acceleration of particle, cosmic ray, Astrophysics::Galaxy Astrophysics, gamma-rays: ISM, ISM: supernova remnants, Physics, radiation mechanisms: nonthermal, 010308 nuclear & particles physics, Astronomy and Astrophysics, nonthermal [radiation mechanisms], gamma-rays, Astronomy and Astrophysic, catalogs, cosmic rays, Space and Planetary Science, Radio, Supernova, [SDU]Sciences of the Universe [physics], 13. Climate action, ddc:520, supernova remnant [ISM], Longitude, acceleration of particles – catalogs – cosmic rays – gamma-rays: ISM – ISM: supernova remnants – radiation mechanisms: nonthermal, Fermi Gamma-ray Space Telescope
Abstract: International audience; To uniformly determine the properties of supernova remnants (SNRs) at high energies, we have developed the first systematic survey at energies from 1 to 100 GeV using data from the Fermi Large Area Telescope (LAT). Based on the spatial overlap of sources detected at GeV energies with SNRs known from radio surveys, we classify 30 sources as likely GeV SNRs. We also report 14 marginal associations and 245 flux upper limits. A mock catalog in which the positions of known remnants are scrambled in Galactic longitude allows us to determine an upper limit of 22% on the number of GeV candidates falsely identified as SNRs. We have also developed a method to estimate spectral and spatial systematic errors arising from the diffuse interstellar emission model, a key component of all Galactic Fermi LAT analyses. By studying remnants uniformly in aggregate, we measure the GeV properties common to these objects and provide a crucial context for the detailed modeling of individual SNRs. Combining our GeV results with multiwavelength (MW) data, including radio, X-ray, and TeV, we demonstrate the need for improvements to previously sufficient, simple models describing the GeV and radio emission from these objects. We model the GeV and MW emission from SNRs in aggregate to constrain their maximal contribution to observed Galactic cosmic rays.
Published: 2016
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68. Search for a correlation between very-high-energy gamma rays and giant radio pulses in the Crab pulsar

Author: Matthias Beilicke, J. P. Dumm, Martin Pohl, G. Tešić, Q. Feng, V. Bugaev, T. Aune, A. Varlotta, R. Dickherber, T. B. Humensky, T. J. N. Nelson, S. Thibadeau, A. McCann, M. P. Connolly, Maxim Lyutikov, R. G. Wagner, Henric Krawczynski, E. Aliu, A. J.R. Weinstein, I. Telezhinsky, Jamie Holder, F. Krennrich, H. Prokoph, S. Vincent, L. C. Reyes, K. Lee, Sinéad M. Griffin, D. B. Saxon, Karen Byrum, D. S. Hanna, N. H. Park, Lucy Fortson, D. Staszak, K. Tsurusaki, M. Theiling, T. C. Arlen, K. Ragan, Gareth Hughes, Amy Furniss, P. Kaaret, M. Schroedter, B. Zitzer, E. Collins-Hughes, Gernot Maier, M. J. Lang, G. H. Gillanders, S. Godambe, S. P. Wakely, G. H. Sembroski, Daniel Gall, R. Welsing, A. N. Otte, Matthew R. Orr, L. Ciupik, A. Cesarini, R. A. Ong, V. Kondratiev, David A. Williams, John L. Quinn, A. Bouvier, J. H. Buckley, A. D. Falcone, J. P. Finley, M. Vivier, T. C. Weekes, S. LeBohec, David Kieda, S. McArthur, Y. Khassen, P. T. Reynolds, Geza Gyuk, Pratik Majumdar, S. Archambault, Reshmi Mukherjee, Wystan Benbow, J. S. Perkins, P. Moriarty, Nicola Galante, J. Grube, N. Karlsson, G. Finnegan, A. W. Smith, A. S Madhavan, C. Duke, E. Roache, G. D. Şentürk, H. Huan, A. O'Faolain de Bhroithe, S. Federici, and Wei Cui
Subjects: High energy, nebula, pulsars: individual: b0531+21, Flux, FOS: Physical sciences, Astrophysics, 01 natural sciences, Arrival time, law.invention, Radio telescope, Telescope, law, Time windows, 0103 physical sciences, emission, photons, rays: stars, geminga, 010303 astronomy & astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), model, 010308 nuclear & particles physics, Crab Pulsar, Gamma ray, Institut für Physik und Astronomie, Astronomy and Astrophysics, telescopes, universe, Space and Planetary Science, range, Astrophysics - High Energy Astrophysical Phenomena
Abstract: We present the results of a joint observational campaign between the Green Bank radio telescope and the VERITAS gamma-ray telescope, which searched for a correlation between the emission of very-high-energy (VHE) gamma rays ($E_{\gamma} >$ 150 GeV) and Giant Radio Pulses (GRPs) from the Crab pulsar at 8.9 GHz. A total of 15366 GRPs were recorded during 11.6 hours of simultaneous observations, which were made across four nights in December 2008 and in November and December 2009. We searched for an enhancement of the pulsed gamma-ray emission within time windows placed around the arrival time of the GRP events. In total, 8 different time windows with durations ranging from 0.033 ms to 72 s were positioned at three different locations relative to the GRP to search for enhanced gamma-ray emission which lagged, led, or was concurrent with, the GRP event. Further, we performed separate searches on main pulse GRPs and interpulse GRPs and on the most energetic GRPs in our data sample. No significant enhancement of pulsed VHE emission was found in any of the preformed searches. We set upper limits of 5-10 times the average VHE flux of the Crab pulsar on the flux simultaneous with interpulse GRPs on single-rotation-period time scales. On $\sim$8-second time scales around interpulse GRPs, we set an upper limit of 2-3 times the average VHE flux. Within the framework of recent models for pulsed VHE emission from the Crab pulsar, the expected VHE-GRP emission correlations are below the derived limits., Comment: 12 pages, 12 figures, To appear in The Astrophysical Journal
Published: 2012
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69. VERITAS Observations of the Nova in V407 Cygni

Author: H. J. Rose, A. Cesarini, John L. Quinn, Gernot Maier, S. Griffin, M. Orr, A. Varlotta, Martin Pohl, D. Staszak, G. Hughes, E. Aliu, S. P. Wakely, J. Dumm, S. Vincent, K. Lee, D. S. Hanna, G. Tešić, M. Theiling, T. Weisgarber, S. M. Bradbury, A. Cannon, P. Kaaret, J. P. Finley, S. Godambe, M. Kertzman, T. B. Humensky, T. C. Weekes, K. Tsurusaki, Geza Gyuk, Dirk Pandel, M. J. Lang, S. Thibadeau, H. Krawczynski, V. Bugaev, T. Arlen, N. Galante, J. Ruppel, M. Schroedter, Vikram V. Dwarkadas, B. Zitzer, G. Finnegan, J. Grube, A. W. Smith, Manel Errando, S. Archambault, Lucy Fortson, G. H. Sembroski, M. Vivier, Abraham D. Falcone, C. Duke, M. Beilicke, Wystan Benbow, J. H. Buckley, David A. Williams, R. Welsing, D. B. Saxon, H. Huan, N. H. Park, K. Ragan, S. McArthur, I. Telezhinsky, David Kieda, Paul D. Nuñez, A. McCann, Wei Cui, Jamie Holder, P. Majumdar, E. Roache, P. Moriarty, J. E. Ward, G. Decerprit, C. Skole, A. Weinstein, H. Prokoph, J. Tyler, Karen Byrum, R. A. Ong, A. N. Otte, M. P. Connolly, Q. Feng, T. Aune, F. Krennrich, J. S. Perkins, E. Collins-Hughes, L. Ciupik, J. Millis, A. Bouvier, P. T. Reynolds, D. Gall, R. Mukherjee, Luis C. Reyes, N. Karlsson, A. Furniss, R. Dickherber, and Y. Khassen
Subjects: High energy, blast wave, FOS: Physical sciences, Radiation imaging, Flux, array, Astrophysics, galactic plane, 01 natural sciences, law.invention, Telescope, law, 0103 physical sciences, novae, cataclysmic variables, 010306 general physics, 010303 astronomy & astrophysics, Zenith, white dwarfs, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Gamma ray, Institut für Physik und Astronomie, Astronomy and Astrophysics, gamma rays: general, Nova (laser), gamma-ray emission, Astrophysics - Astrophysics of Galaxies, rs-ophiuchi, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), cherenkov telescopes, Astrophysics - High Energy Astrophysical Phenomena, 2006 outburst, discovery
Abstract: We report on very high energy (E > 100 GeV) gamma-ray observations of V407 Cygni, a symbiotic binary that underwent a nova outburst producing 0.1-10 GeV gamma rays during 2010 March 10-26. Observations were made with the Very Energetic Radiation Imaging Telescope Array System during 2010 March 19-26 at relatively large zenith angles, due to the position of V407 Cyg. An improved reconstruction technique for large zenith angle observations is presented and used to analyze the data. We do not detect V407 Cygni and place a differential upper limit on the flux at 1.6 TeV of 2.3 \times 10^(-12) erg cm^(-2) s^(-1) (at the 95% confidence level). When considered jointly with data from Fermi-LAT, this result places limits on the acceleration of very high energy particles in the nova., 17 pages, 4 figures, accepted for publication in ApJ
Published: 2012
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70. Discovery of High-energy and Very High Energy Gamma-ray Emission from the Blazar RBS 0413

Author: D. Gall, M. P. Connolly, R. Mukherjee, G. H. Sembroski, S. McArthur, T. B. Humensky, S. Archambault, S. Griffin, P. Fortin, H. J. Rose, A. Pichel, P. T. Reynolds, J. E. Ward, A. Cesarini, A. N. Otte, John L. Quinn, A. S. Madhavan, Wystan Benbow, A. Varlotta, P. Majumdar, I. Telezhinsky, J. Grube, R. A. Ong, Manel Errando, Jamie Holder, A. Bouvier, M. J. Lang, M. Theiling, J. P. Finley, S. M. Bradbury, K. Ragan, Wei Cui, S. Thibadeau, T. Aune, Markus Böttcher, T. C. Weekes, Abraham D. Falcone, G. Decerprit, L. C. Reyes, A. McCann, H. Prokoph, E. Roache, N. Palma, Geza Gyuk, G. Tešić, E. Aliu, D. Horan, J. Ruppel, L. Ciupik, Gareth Hughes, M. Kertzman, B. Zitzer, T. Weisgarber, K. Lee, D. S. Hanna, V. Bugaev, A. Weinstein, M. Vivier, David A. Williams, H. Krawczynski, K. Tsurusaki, S. Godambe, T. Arlen, Lucy Fortson, Martin Pohl, J. Dumm, Keith Hawkins, Karen Byrum, M. Schroedter, M. Beilicke, David Kieda, J. H. Buckley, J. S. Perkins, E. Collins-Hughes, F. Krennrich, M. Orr, Q. Feng, A. Cannon, P. Kaaret, D. B. Saxon, N. H. Park, Gernot Maier, S. P. Wakely, N. Galante, G. Finnegan, A. W. Smith, G. D. Şentürk, H. Huan, Paolo De Coppi, P. Moriarty, A. Furniss, D. Staszak, R. Dickherber, Y. Khassen, and N. Karlsson
Subjects: catalog, Astrophysics::High Energy Astrophysical Phenomena, bl-lacertae objects, Flux, FOS: Physical sciences, Astrophysics, swift ultraviolet/optical telescope, bright blazars, 7. Clean energy, 01 natural sciences, law.invention, Telescope, law, gamma rays: galaxies, 0103 physical sciences, bl lacertae objects: individual (rbs 0413-ver j0319+187), Blazar, Nuclear Experiment, 010303 astronomy & astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), model, 010308 nuclear & particles physics, Institut für Physik und Astronomie, Astronomy and Astrophysics, lac objects, Synchrotron, radiation, large-area telescope, Crab Nebula, mission, 13. Climate action, Space and Planetary Science, active galactic nuclei, Spectral energy distribution, High Energy Physics::Experiment, Astrophysics - High Energy Astrophysical Phenomena, BL Lac object, Fermi Gamma-ray Space Telescope
Abstract: We report on the discovery of high-energy (HE; E > 0.1 GeV) and very high-energy (VHE; E > 100 GeV) gamma-ray emission from the high-frequency-peaked BL Lac object RBS 0413. VERITAS, a ground-based gamma-ray observatory, detected VHE gamma rays from RBS 0413 with a statistical significance of 5.5 standard deviations (sigma) and a gamma-ray flux of (1.5 \pm 0.6stat \pm 0.7syst) \times 10^(-8) photons m^(-2) s^(-1) (\sim 1% of the Crab Nebula flux) above 250 GeV. The observed spectrum can be described by a power law with a photon index of 3.18 \pm 0.68stat \pm 0.30syst. Contemporaneous observations with the Large Area Telescope (LAT) on the Fermi Gamma-ray Space Telescope detected HE gamma rays from RBS 0413 with a statistical significance of more than 9 sigma, a power-law photon index of 1.57 \pm 0.12stat +0.11sys -0.12sys and a gamma-ray flux between 300 MeV and 300 GeV of (1.64 \pm 0.43stat +0.31sys -0.22sys) \times 10^(-5) photons m^(-2) s^(-1). We present the results from Fermi-LAT and VERITAS, including a spectral energy distribution modeling of the gamma-ray, quasi-simultaneous X-ray (Swift-XRT), ultraviolet (Swift-UVOT) and R-band optical (MDM) data. We find that, if conditions close to equipartition are required, both the combined synchrotron self-Compton/external-Compton and the lepto-hadronic models are preferred over a pure synchrotron self-Compton model., 14 pages, 3 figures, accepted to ApJ, corresponding author: G. D. Senturk
Published: 2012
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71. VERITAS deep observations of the dwarf spheroidal galaxy Segue 1

Author: A. McCann, I. Telezhinsky, R. A. Ong, Jamie Holder, T. Arlen, G. Teić, Philip Kaaret, A. S. Madhavan, Wystan Benbow, S. Vincent, N. Galante, G. D. Entürk, A. Bouvier, G. H. Sembroski, S. McArthur, G. Finnegan, A. W. Smith, S. M. Bradbury, Gernot Maier, M. P. Connolly, S. P. Wakely, Abraham D. Falcone, A. Varlotta, T. Aune, J. Grube, A. Cannon, E. Roache, H. Huan, Matthew R. Orr, R. Dickherber, Manel Errando, Daniel Gall, Karen Byrum, K. Ragan, S. Thibadeau, J. H. Buckley, E. Collins-Hughes, M. Kertzman, Lucy Fortson, J. S. Perkins, H. J. Rose, G. Decerprit, V. Bugaev, Q. Feng, P. Moriarty, M. Vivier, M. Beilicke, M. Schroedter, David A. Williams, Y. Khassen, T. Weisgarber, D. Staszak, J. E. Ward, S. Archambault, Reshmi Mukherjee, T. B. Humensky, A. Furniss, Francesc Ferrer, Geza Gyuk, D. B. Saxon, A. Cesarini, John L. Quinn, B. Zitzer, P. T. Reynolds, N. H. Park, Henric Krawczynski, L. Ciupik, P. Majumdar, E. Aliu, K. Tsurusaki, Jodi Christiansen, C. Skole, D. Hanna, Martin Pohl, S. Godambe, J. Dumm, K. Lee, L. C. Reyes, Vladimir Vassiliev, N. Karlsson, J. P. Finley, T. C. Weekes, Wei Cui, H. Prokoph, R. G. Wagner, David Kieda, M. Theiling, J. Ruppel, Amanda Weinstein, A. N. Otte, Frank Krennrich, Sinéad M. Griffin, and Gareth Hughes
Subjects: Nuclear and High Energy Physics, Astrophysics::High Energy Astrophysical Phenomena, Dwarf galaxy problem, cosmic-rays, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, dark-matter annihilation, 01 natural sciences, local group, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, upper limits, ddc:530, 010303 astronomy & astrophysics, Light dark matter, galactic-center, Astrophysics::Galaxy Astrophysics, Dwarf galaxy, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, 010308 nuclear & particles physics, Hot dark matter, Institut für Physik und Astronomie, Astronomy, Segue, gamma-ray emission, Galaxy, Dwarf spheroidal galaxy, Dark matter halo, large-area telescope, cherenkov telescopes, Astrophysics - High Energy Astrophysical Phenomena, magic telescope, empirical-models
Abstract: The VERITAS array of Cherenkov telescopes has carried out a deep observational program on the nearby dwarf spheroidal galaxy Segue 1. We report on the results of nearly 48 hours of good quality selected data, taken between January 2010 and May 2011. No significant $\gamma$-ray emission is detected at the nominal position of Segue 1, and upper limits on the integrated flux are derived. According to recent studies, Segue 1 is the most dark matter-dominated dwarf spheroidal galaxy currently known. We derive stringent bounds on various annihilating and decaying dark matter particle models. The upper limits on the velocity-weighted annihilation cross-section are $\mathrm{^{95% CL} \lesssim 10^{-23} cm^{3} s^{-1}}$, improving our limits from previous observations of dwarf spheroidal galaxies by at least a factor of two for dark matter particle masses $\mathrm{m_{\chi}\gtrsim 300 GeV}$. The lower limits on the decay lifetime are at the level of $\mathrm{\tau^{95% CL} \gtrsim 10^{24} s}$. Finally, we address the interpretation of the cosmic ray lepton anomalies measured by ATIC and PAMELA in terms of dark matter annihilation, and show that the VERITAS observations of Segue 1 disfavor such a scenario., Comment: Added recently published erratum at the end of the original article
Published: 2012
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72. The detection at high and very high energies of the blazar 1ES 1312-423

Author: J. Biteau, Y. Becherini, D. A. Sanchez, J. S. Perkins, null H.E.S.S. Collaboration, and null Fermi-LAT Collaboration
Subjects: Physics, Radio galaxy, Astrophysics::High Energy Astrophysical Phenomena, Centaurus A, Astronomy, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Galaxy, law.invention, Telescope, law, Spectral energy distribution, High Energy Stereoscopic System, Blazar, Astrophysics::Galaxy Astrophysics, Fermi Gamma-ray Space Telescope
Abstract: The deep observation campaign led on Centaurus A with the High Energy Stereoscopic System (H.E.S.S.) has revealed a significant very high energy (VHE, E ≥ 100 GeV) excess coincident with the blazar 1ES 1312-423, 2° away from the radio galaxy. The source is also detected at high energy (HE, 20 MeV-300 GeV) with the Fermi Large Area Telescope (Fermi-LAT) after 3.5 years of all-sky monitoring. The high and very high energy spectra, together with Swift-XRT and ATOM observations are used to draw the first broad band spectral energy distribution (SED) of 1ES 1312-423. The non-thermal emission of this faint HBL is reproduced with a synchrotron self-Compton (SSC) model combined with a black-body spectrum for the host galaxy.
Published: 2012
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73. Veritas observations of day-scale flaring of M 87 in 2010 April

Author: R. Dickherber, A. Cesarini, John L. Quinn, S. Thibadeau, Sinéad M. Griffin, M. Kertzman, J. P. Finley, K. Tsurusaki, H. Prokoph, P. Kaaret, Geza Gyuk, J. Ruppel, R. Guenette, T. C. Weekes, Pratik Majumdar, A. Pichel, S. Godambe, Nahee Park, Reshmi Mukherjee, M. P. Connolly, A. McCann, H. J. Rose, K. L. Byrum, E. Collins-Hughes, J. Tyler, N. Karlsson, J. H. Buckley, E. Aliu, A. N. Otte, David A. Williams, Gernot Maier, L. Ciupik, G. Tešić, C. M. Hui, Wystan Benbow, Jamie Holder, Henric Krawczynski, Daniel Gall, A. Varlotta, M. J. Lang, A. J.R. Weinstein, L. C. Reyes, C. Skole, Amy Furniss, Matthias Beilicke, M. Pohl, Wei Cui, D. Staszak, Paul D. Nuñez, S. M. Bradbury, K. Ragan, R. A. Ong, Thomas Weisgarber, Matthew R. Orr, S. P. Wakely, V. V. Vassiliev, G. Hughes, F. Krennrich, A. D. Falcone, A. Bouvier, J. S. Perkins, S. LeBohec, J. E. Ward, A. Cannon, M. Theiling, Lucy Fortson, D. B. Saxon, T. Aune, S. McArthur, V. Bugaev, G. H. Sembroski, T. B. Humensky, B. Zitzer, Manel Errando, D. B. Kieda, G. Finnegan, A. S Madhavan, C. Duke, E. Roache, G. D. Şentürk, H. Huan, P. Moriarty, Nicola Galante, J. Grube, D. S. Hanna, T. C. Arlen, A. Imran, P. T. Reynolds, M. Schroedter, S. Vincent, and M. Vivier
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO), Radio galaxy, Ciencias Físicas, Phase (waves), FOS: Physical sciences, Flux, radio galaxy m87, Astrophysics, Electron, telescope, agns, 01 natural sciences, 7. Clean energy, Spectral line, blazar, law.invention, purl.org/becyt/ford/1 [https], law, jet, gamma rays: galaxies, 0103 physical sciences, galaxies: individual (m 87, ver j1230+123), hst-1, 010303 astronomy & astrophysics, Physics, Spectral index, tev emission, variability, 010308 nuclear & particles physics, Institut für Physik und Astronomie, Astronomy and Astrophysics, purl.org/becyt/ford/1.3 [https], gamma-ray emission, Astronomía, Space and Planetary Science, individual (M 87, VER J1230+123) [galaxies], Rise time, galaxies [gamma rays], CIENCIAS NATURALES Y EXACTAS, supermassive black-hole, Astrophysics - Cosmology and Nongalactic Astrophysics, Flare
Abstract: VERITAS has been monitoring the very-high-energy (VHE; >100GeV) gamma-ray activity of the radio galaxy M87 since 2007. During 2008, flaring activity on a timescale of a few days was observed with a peak flux of (0.70 +- 0.16) X 10^{-11} cm^{-2} s^{-1} at energies above 350GeV. In 2010 April, VERITAS detected a flare from M87 with peak flux of (2.71 +- 0.68) X 10^{-11} cm^{-2} s^{-1} for E>350GeV. The source was observed for six consecutive nights during the flare, resulting in a total of 21 hr of good quality data. The most rapid flux variation occurred on the trailing edge of the flare with an exponential flux decay time of 0.90^{+0.22}_{-0.15} days. The shortest detected exponential rise time is three times as long, at 2.87^{+1.65}_{-0.99} days. The quality of the data sample is such that spectral analysis can be performed for three periods: rising flux, peak flux, and falling flux. The spectra obtained are consistent with power-law forms. The spectral index at the peak of the flare is equal to 2.19 +- 0.07. There is some indication that the spectrum is softer in the falling phase of the flare than the peak phase, with a confidence level corresponding to 3.6 standard deviations. We discuss the implications of these results for the acceleration and cooling rates of VHE electrons in M87 and the constraints they provide on the physical size of the emitting region., Accepted for publication in ApJ; 17 pages, 5 figures; Corresponding author: C. M. Hui
Published: 2012
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74. Multiwavelength observations of the AGN 1ES 0414+009 with veritas, FERMI-LAT, SWIFT-XRT, AND MDM

Author: E. Aliu, S. Archambault, T. Arlen, T. Aune, M. Beilicke, W. Benbow, M. Böttcher, A. Bouvier, V. Bugaev, A. Cannon, A. Cesarini, L. Ciupik, E. Collins-Hughes, M. P. Connolly, W. Cui, R. Dickherber, J. Dumm, M. Errando, A. Falcone, S. Federici, Q. Feng, J. P. Finley, G. Finnegan, L. Fortson, A. Furniss, N. Galante, D. Gall, S. Godambe, S. Griffin, J. Grube, G. Gyuk, D. Hanna, J. Holder, H. Huan, G. Hughes, C. M. Hui, A. Imran, O. Jameil, P. Kaaret, N. Karlsson, M. Kertzman, J. Kerr, Y. Khassen, D. Kieda, H. Krawczynski, F. Krennrich, M. J. Lang, K. Lee, A. S. Madhavan, P. Majumdar, S. McArthur, A. McCann, P. Moriarty, R. Mukherjee, T. Nelson, A. O'Faoláin de Bhróithe, R. A. Ong, M. Orr, A. N. Otte, N. Park, J. S. Perkins, A. Pichel, M. Pohl, J. Quinn, K. Ragan, P. T. Reynolds, E. Roache, J. Ruppel, D. B. Saxon, M. Schroedter, G. H. Sembroski, G. D. Şentürk, A. W. Smith, D. Staszak, M. Stroh, I. Telezhinsky, G. Tešić, M. Theiling, S. Thibadeau, K. Tsurusaki, A. Varlotta, V. V. Vassiliev, M. Vivier, S. P. Wakely, J. E. Ward, A. Weinstein, R. Welsing, D. A. Williams, and B. Zitzer
Subjects: stars, Photon, Ciencias Físicas, Astrophysics::High Energy Astrophysical Phenomena, blazars, Flux, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, telescope, 01 natural sciences, Power law, purl.org/becyt/ford/1 [https], gamma-ray astronomy, 0103 physical sciences, gamma rays: galaxies, emission, bl lacertae objects: individual (1es 0414+009, erj0416+011), Nuclear Experiment, 010303 astronomy & astrophysics, Cherenkov radiation, Physics, search, High Energy Astrophysical Phenomena (astro-ph.HE), 010308 nuclear & particles physics, Institut für Physik und Astronomie, Astronomy and Astrophysics, purl.org/becyt/ford/1.3 [https], sample, Astronomía, Crab Nebula, individual (1ES 0414+009, VERJ0416+011) [BL Lacertae objects], Space and Planetary Science, bl lacertae object, galaxies [gamma rays], Spectral energy distribution, High Energy Physics::Experiment, Astrophysics - High Energy Astrophysical Phenomena, CIENCIAS NATURALES Y EXACTAS, discovery, Fermi Gamma-ray Space Telescope, BL Lac object
Abstract: We present observations of the BL Lac object 1ES 0414+009 in the >200 GeV gamma-ray band by the VERITAS array of Cherenkov telescopes. 1ES 0414+009 was observed by VERITAS between January 2008 and February 2011, resulting in 56.2 hours of good quality pointed observations. These observations resulted in a detection of 822 events from the source corresponding to a statistical significance of 6.4 standard deviations (6.4 sigma) above the background. The source flux, showing no evidence for variability, is measured as 5.2 +/- 1.1_stat +/- 2.6_sys * 10^-12 photons cm^-2 s^-1 above 200 GeV, equivalent to approximately 2% of the Crab Nebula flux above this energy. The differential photon spectrum from 230 GeV to 850 GeV is well fit by a power law with an photon index of Gamma 3.4 +/- 0.5_stat +/- 0.3_sys and a flux normalization of 1.6 +/- 0.3_stat +/- 0.8_sys * 10^-11 photons cm^-2 s^-1 at 300 GeV. We also present multiwavelength results taken in the optical (MDM), X-ray (Swift-XRT), and GeV (Fermi-LAT) bands and use these results to construct a broadband spectral energy distribution (SED). Modeling of this SED indicates that homogenous one-zone leptonic scenarios are not adequate to describe emission from the system, with a lepto-hadronic model providing a better fit to the data., Accepted for publication in The Astrophysical Journal
Published: 2012
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75. VERITAS Observations of Six Bright, Hard-Spectrum Fermi-LAT Blazars

Author: S. McArthur, Martin Pohl, T. Aune, J. Dumm, A. O'Faolain de Bhroithe, H. Krawczynski, D. B. Saxon, S. Griffin, A. N. Otte, D. S. Hanna, S. Thibadeau, Jason X. Prochaska, N. H. Park, R. A. Ong, Markus Böttcher, D. Horan, A. Bouvier, F. Krennrich, J. H. Buckley, M. Orr, Wystan Benbow, L. Ciupik, P. T. Reynolds, Gernot Maier, K. Ragan, S. P. Wakely, H. Prokoph, V. V. Vassiliev, N. Galante, S. Vincent, Abraham D. Falcone, D. Gall, David A. Williams, R. Mukherjee, J. S. Perkins, A. Pichel, E. Collins-Hughes, P. Fortin, T. Arlen, M. P. Connolly, G. Finnegan, A. McCann, B. Zitzer, A. Cesarini, A. S Madhavan, C. Duke, Q. Feng, John L. Quinn, E. Aliu, A. Varlotta, Geza Gyuk, Lucy Fortson, H. Huan, K. Lee, Pratik Majumdar, J. Grube, Manel Errando, Kyle F. Kaplan, I. Telezhinsky, Jamie Holder, J. P. Finley, E. Roache, A. Furniss, L. C. Reyes, T. C. Weekes, R. Dickherber, G. H. Sembroski, R. Welsing, D. Staszak, Michele Fumagalli, Y. Khassen, P. Kaaret, N. Karlsson, S. Federici, P. Moriarty, Wei Cui, S. Archambault, M. Theiling, G. Tešić, T. J. N. Nelson, V. Bugaev, A. Weinstein, M. Vivier, M. Beilicke, David Kieda, K. Tsurusaki, S. Godambe, Aliu, E, Archambault, S, Arlen, T, Aune, T, Beilicke, M, Benbow, W, Bottcher, M, Bouvier, A, Buckley, J, Bugaev, V, Cesarini, A, Ciupik, L, Collins-Hughes, E, Connolly, M, Cui, W, Dickherber, R, Duke, C, Dumm, J, Errando, M, Falcone, A, Federici, S, Feng, Q, Finley, J, Finnegan, G, Fortson, L, Furniss, A, Galante, N, Gall, D, Godambe, S, Griffin, S, Grube, J, Gyuk, G, Hanna, D, Holder, J, Huan, H, Kaaret, P, Karlsson, N, Khassen, Y, Kieda, D, Krawczynski, H, Krennrich, F, Lee, K, Madhavan, A, Maier, G, Majumdar, P, Mcarthur, S, Mccann, A, Moriarty, P, Mukherjee, R, Nelson, T, De Bhroithe, A, Ong, R, Orr, M, Otte, A, Park, N, Perkins, J, Pichel, A, Pohl, M, Prokoph, H, Quinn, J, Ragan, K, Reyes, L, Reynolds, P, Roache, E, Saxon, D, Sembroski, G, Staszak, D, Telezhinsky, I, Tesic, G, Theiling, M, Thibadeau, S, Tsurusaki, K, Varlotta, A, Vassiliev, V, Vincent, S, Vivier, M, Wakely, S, Weekes, T, Weinstein, A, Welsing, R, Williams, D, Zitzer, B, Fortin, P, Horan, D, Fumagalli, M, Kaplan, K, and Prochaska, J
Subjects: Ciencias Físicas, Astrophysics::High Energy Astrophysical Phenomena, media_common.quotation_subject, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, 01 natural sciences, 7. Clean energy, law.invention, purl.org/becyt/ford/1 [https], Telescope, law, 0103 physical sciences, gamma rays: galaxie, Astrophysics::Solar and Stellar Astrophysics, Blazar, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, media_common, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, general [BL Lacertae objects], 010308 nuclear & particles physics, Astrophysics::Instrumentation and Methods for Astrophysics, Institut für Physik und Astronomie, Spectral density, Astronomy and Astrophysics, BL Lacertae objects: general, purl.org/becyt/ford/1.3 [https], Synchrotron, Redshift, Astronomía, Extragalactic background light, Space and Planetary Science, Sky, galaxies [gamma rays], Astrophysics - High Energy Astrophysical Phenomena, CIENCIAS NATURALES Y EXACTAS, Fermi Gamma-ray Space Telescope
Abstract: We report on VERITAS very high energy (VHE; E > 100 GeV) observations of six blazars selected from the Fermi Large Area Telescope First Source Catalog (1FGL). The gamma-ray emission from 1FGL sources was extrapolated up to the VHE band, taking gamma-ray absorption by the extragalactic background light into account. This allowed the selection of six bright, hard-spectrum blazars that were good candidate TeV emitters. Spectroscopic redshift measurements were attempted with the Keck Telescope for the targets without Sloan Digital Sky Survey spectroscopic data. No VHE emission is detected during the observations of the six sources described here. Corresponding TeV upper limits are presented, along with contemporaneous Fermi observations and non-concurrent Swift UVOT and X-Ray Telescope data. The blazar broadband spectral energy distributions (SEDs) are assembled and modeled with a single-zone synchrotron self-Compton model. The SED built for each of the six blazars shows a synchrotron peak bordering between the intermediate- and high-spectrum-peak classifications, with four of the six resulting in particle-dominated emission regions. Fil: Aliu, E.. Columbia University; Estados Unidos Fil: Archambault, S.. McGill University; Canadá Fil: Arlen, T.. University of California; Estados Unidos Fil: Aune, E.. University of California; Estados Unidos Fil: Beilicke, M.. University of Washington; Estados Unidos Fil: Benbow, W.. Harvard-Smithsonian Center for Astrophysics; Estados Unidos Fil: Bottcher, M.. Ohio University; Estados Unidos Fil: Bouvier, A.. University of California; Estados Unidos Fil: Buckley, J. H.. University of Washington; Estados Unidos Fil: Bugaev, V.. University of Washington; Estados Unidos Fil: Cesarini, A.. National University of Ireland Galway; Irlanda Fil: Ciupik, L.. Adler Planetarium and Astronomy Museum; Estados Unidos Fil: Collin Hughes, E.. University College Dublin; Irlanda Fil: Connolly, M. P.. National University of Ireland Galway; Irlanda Fil: Cui, W.. Purdue University; Estados Unidos Fil: Dickherber, R.. University of Washington; Estados Unidos Fil: Duke, C.. Grinnell College; Estados Unidos Fil: Dumm, J.. University Of Minnesota; Estados Unidos Fil: Errando, M.. Columbia University; Estados Unidos Fil: Falcone, A.. University of Pennsylvania; Estados Unidos Fil: Federici, S.. Desy; Alemania Fil: Feng, Q.. Purdue University; Estados Unidos Fil: Finley, J. P.. Purdue University; Estados Unidos Fil: Finnegan, G.. University of Utah; Estados Unidos Fil: Fortson, L.. University Of Minnesota; Estados Unidos Fil: Furniss, A.. University of California; Estados Unidos Fil: Galante, N.. Harvard-Smithsonian Center for Astrophysics; Estados Unidos Fil: Gall, D.. University of Iowa; Estados Unidos Fil: Godambe, S.. University of Utah; Estados Unidos Fil: Griffin, S.. McGill University; Canadá Fil: Pichel, Ana Carolina. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentina Fil: The Veritas Collaboration.
Published: 2012
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76. Constraints on Cosmic Rays, Magnetic Fields, and Dark Matter from Gamma-Ray Observations of the Coma Cluster of Galaxies with VERITAS and Fermi

Author: T. Arlen, T. Aune, M. Beilicke, W. Benbow, A. Bouvier, J. H. Buckley, V. Bugaev, K. Byrum, A. Cannon, A. Cesarini, L. Ciupik, E. Collins-Hughes, M. P. Connolly, W. Cui, R. Dickherber, J. Dumm, A. Falcone, S. Federici, Q. Feng, J. P. Finley, G. Finnegan, L. Fortson, A. Furniss, N. Galante, D. Gall, S. Godambe, S. Griffin, J. Grube, G. Gyuk, J. Holder, H. Huan, G. Hughes, T. B. Humensky, A. Imran, P. Kaaret, N. Karlsson, M. Kertzman, Y. Khassen, D. Kieda, H. Krawczynski, F. Krennrich, K. Lee, A. S Madhavan, G. Maier, P. Majumdar, S. McArthur, A. McCann, P. Moriarty, R. Mukherjee, T. Nelson, A. O’Faoláin de Bhróit, R. A. Ong, M. Orr, A. N. Otte, N. Park, J. S. Perkins, M. Pohl, H. Prokoph, J. Quinn, K. Ragan, L. C. Reyes, P. T. Reynolds, E. Roache, J. Ruppel, D. B. Saxon, M. Schroedter, G. H. Sembroski, C. Skole, A. W. Smith, I. Telezhinsky, G. Tešić, M. Theiling, S. Thibadeau, K. Tsurusaki, A. Varlotta, M. Vivier, S. P. Wakely, J. E. Ward, A. Weinstein, R. Welsing, D. A. Williams, B. Zitzer, C. Pfrommer, and A. Pinzke
Subjects: Cosmology and Nongalactic Astrophysics (astro-ph.CO), Astrophysics::High Energy Astrophysical Phenomena, Dark matter, nonthermal emission, FOS: Physical sciences, Coma (optics), Cosmic ray, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, galaxies: clusters: individual (coma (aco 1656)), magnetic fields, dark matter, large-scale structure, shock-waves, atmospheric cherenkov telescopes, diffuse radio-emission, cosmic rays, all-sky survey, Coma Cluster, upper limits, galactic-center, Galaxy cluster, Cherenkov radiation, gamma rays: galaxies: clusters, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Institut für Physik und Astronomie, Astronomy and Astrophysics, source catalog, Galaxy, x-ray, galaxies: clusters: general, Space and Planetary Science, Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Nongalactic Astrophysics, Fermi Gamma-ray Space Telescope
Abstract: Observations of radio halos and relics in galaxy clusters indicate efficient electron acceleration. Protons should likewise be accelerated, suggesting that clusters may also be sources of very high-energy (VHE; E>100 GeV) gamma-ray emission. We report here on VHE gamma-ray observations of the Coma galaxy cluster with the VERITAS array of imaging Cherenkov telescopes, with complementing Fermi-LAT observations at GeV energies. No significant gamma-ray emission from the Coma cluster was detected. Integral flux upper limits at the 99% confidence level were measured to be on the order of (2-5)*10^-8\ ph. m^-2 s^-1 (VERITAS, >220 GeV} and ~2*10^-6 ph. m^-2 s^-1 (Fermi, 1-3 GeV), respectively. We use the gamma-ray upper limits to constrain CRs and magnetic fields in Coma. Using an analytical approach, the CR-to-thermal pressure ratio is constrained to be < 16% from VERITAS data and < 1.7% from Fermi data (averaged within the virial radius). These upper limits are starting to constrain the CR physics in self-consistent cosmological cluster simulations and cap the maximum CR acceleration efficiency at structure formation shocks to be, ApJ in press
Published: 2012
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77. VERY HIGH ENERGY γ -RAYS FROM THE UNIVERSE’S MIDDLE AGE: DETECTION OF THE z = 0.940 BLAZAR PKS 1441+25 WITH MAGIC

Author: M. Pesce Rollins, Lluis Font, Francesco Longo, Abelardo Moralejo, I. Snidaric, Thomas Bretz, M. Feige, E. Moretti, Mosè Mariotti, A.-K. Overkemping, M. Makariev, D. Wolfert, E. Lorenz, Max Ludwig Ahnen, S. Haarto, P. Giammaria, T. Steinbring, S. Maldera, F. de Palma, D. Dominis Prester, Nicola Omodei, Marcel Strzys, P. Haeusner, R. Clavero, W. Bednarek, Fabrizio Tavecchio, R. Reinthal, R. Zanin, Elina Lindfors, D. Nakajima, Daniela Dorner, Adrian Biland, P. G. Prada Moroni, R. A. Cameron, M. Gaug, M. Caragiulo, Johan Bregeon, Saverio Lombardi, Kyoshi Nishijima, Arka Chatterjee, D. Fidalgo, U. Barres de Almeida, Damir Lelas, J. Kushida, Daniel Mazin, Igor V. Moskalenko, Olaf Reimer, Julie McEnery, Anne Lähteenmäki, Hiromitsu Takahashi, Julian Sitarek, A. López Oramas, J. Herrera, Wolfgang Rhode, J. Rico, J. Klamt, Dorota Sobczyńska, Jose Luis Contreras, Hiroyasu Tajima, X. Paredes Fortuny, Koji Noda, J. Li, A. Niedzwiecki, Masahiro Teshima, P. Bruel, E. Orlando, Yusuke Konno, T. Toyama, E. Recillas, V. Fallah Ramazani, Elisa Bernardini, K. S. Wood, Carmelo Sgrò, Riccardo Rando, Nikola Godinovic, T. Ohsugi, Eleonora Troja, Juan Cortina, D. J. Thompson, F. Di Pierro, Benito Marcote, P. Fusco, E. Colombo, Stefano Ansoldi, Ievgen Vovk, Oscar Blanch, N. Zottmann, E. Hays, Talvikki Hovatta, Riccardo Paoletti, M. Razzano, Ivica Puljak, E. Nuss, David Paneque, C. Delgado Mendez, Filippo D'Ammando, F. Piron, Pierre Colin, B. De Lotto, Stefano Covino, A. De Angelis, Luigi Pacciani, A. Treves, Vitaly Neustroev, T. Schweizer, M. Kuss, R. Bonino, J. Palacio, R. Mirzoyan, I. A. Grenier, P. Temnikov, Stefano Ciprini, E. de Oña Wilhelmi, Nestor Mirabal, P. Da Vela, L. Carrasco, Marcello Giroletti, L. O. Takalo, D. Guberman, M. I. Martínez, J. M. Paredes, E. Cavazzuti, M. Mayer, Juri Poutanen, S. Rainò, Antonio Stamerra, F. Borracci, Tsunefumi Mizuno, Y. Hanabata, A. González Muñoz, G. Maneva, Marina Manganaro, P. Spinelli, S. Bonnefoy, Kari Nilsson, T. A. Porter, Gloria Spandre, J. Hose, P. Antoranz, Tomoki Saito, D. Tescaro, D. Galindo, U. Menzel, E. Prandini, M. Will, G. Chiaro, Marco Ajello, J. B. Thayer, Merja Tornikoski, F. Loparco, Markus Garczarczyk, Francesco Giordano, B. Banerjee, Sabrina Einecke, D. Elsaesser, J. W. Hewitt, R. Desiante, D. Garrido Terrats, A. Fernández Barral, Diego F. Torres, James Chiang, H. Takami, M. Palatiello, S. Buson, Alessandro Carosi, J. Rodriguez Garcia, P. Lubrano, Mislav Baloković, A. Carraminana, Konstancja Satalecka, A. Sillanpää, L. Di Venere, Dario Gasparrini, Michele Doro, Roger Blandford, Vassil Verguilov, Roopesh Ojha, L. Maraschi, Francesco Dazzi, Ana Babić, Gareth Hughes, F. Spada, Julia Thaele, Tomislav Terzić, A. Porras, M. E. Monzani, A. Morselli, Jose Miguel Miranda, G. A. Caliandro, A. Reimer, W. Idec, A. Hahn, E. Carmona, Stefan Larsson, J. Kania, M. Hayashida, Wu M. H., Steven N. Shore, C. Lorey, Marc Ribó, P. Bangale, E. J. Siskind, Hidetoshi Kubo, Dario Hrupec, M. A. Lopez, G. Bonnoli, F. Gargano, K. Mallot, R. J. García López, R. Lopez Coto, Massimo Persic, V. H. Chavushyan, Liang Li, Guido Barbiellini, J. León Tavares, Pratik Majumdar, M. V. Fonseca, K. Kodani, Reiko Orito, Aaron Dominguez, Juan Abel Barrio, Luca Baldini, J. E. Ward, Sylvain Guiriec, Mn Mazziotta, Christian Fruck, J. S. Perkins, Nicola Giglietto, B. Biasuzzi, M. N. Lovellette, P. A. Caraveo, J. Becerra González, Elisabetta Bissaldi, G. Pivato, Andrei Berdyugin, T. Jogler, Ronaldo Bellazzini, C. Schultz, Louis Antonelli, K. Frantzen, Denis Bastieri, S. Paiano, Karl Mannheim, A. La Barbera, D. Eisenacher Glawion, M. Nievas Rosillo, Universitat de Barcelona, Laboratoire Leprince-Ringuet (LLR), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Laboratoire Univers et Particules de Montpellier (LUPM), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), ITA, USA, GBR, FRA, DEU, ESP, AFG, ALB, DZA, AND, AGO, BGR, BFA, BDI, KHM, CMR, CAN, CPV, CS, TCD, CYM, COD, CHL, TWN, CYP, VAT, COL, COM, COG, PRK, KOR, CIV, DOM, CCK, CRI, HRV, CUB, DNK, DMA, ECU, EGY, SLV, ARE, CHN, ERI, AIA, EST, ETH, FJI, PHL, FIN, GAB, GMB, GAZA, ZAF, GEO, COK, GHA, JAM, JPN, GIB, DJI, JOR, GRC, REU, GRD, GRL, GLP, FRO, GUM, GTM, GIN, GNB, GNQ, GUI, ROU, GUY, GUF, HTI, HND, FLK, HKG, IND, IDN, IRN, MNP, RWA, MHL, MUS, UMI, SLB, TCA, VIR, ATA, VGB, ISR, KAZ, RUS, KGZ, KIR, SCG, KWT, LAO, LSO, LVA, ATG, LBN, LBR, ESH, LBY, LIE, LTU, LUX, MAC, MKD, MDG, MWI, ANT, MDV, AUS, MYS, MLI, MLT, MAR, MTQ, MRT, MYT, MEX, MDA, SAU, IRQ, MCO, MNG, MSR, MOZ, MMR, NAM, NRU, NPL, NIC, NER, KNA, ARG, NGA, NIU, NOR, NCL, NZL, OMN, NLD, PAK, PLW, SPM, PAN, ARM, PNG, PRY, PER, PCN, PYF, POL, PRI, PRT, VCT, QAT, CZE, ABW, CAF, ASM, WSM, SMR, LCA, SHN, STP, SEN, IRL, AUT, SYC, SLE, SGP, SYR, SVK, SVN, SOM, LKA, ISL, FSM, AZE, SGS, SDN, SUR, SJM, SWE, CHE, SWZ, TJK, BVT, TZA, IOT, BHS, ATF, PSE, THA, TLS, TGO, TKL, TON, MAN, TTO, TUN, TUR, BHR, TKM, TUV, UKR, UGA, HUN, URY, CXR, UZB, VUT, VEN, VNM, BGD, WLF, YEM, ZMB, ZWE, BRB, HMD, BEL, BLZ, BEN, BMU, BTN, BLR, BOL, BIH, BWA, BRA, NFK, BRN, Ahnen, M. L., Ansoldi, S., Antonelli, L. A., Antoranz, P., Babic, A., Banerjee, B., Bangale, P., De Almeida, U. Barre, Barrio, J. A., Bednarek, W., Bernardini, E., Biasuzzi, B., Biland, A., Blanch, O., Bonnefoy, S., Bonnoli, G., Borracci, F., Bretz, T., Carmona, E., Carosi, A., Chatterjee, A., Clavero, R., Colin, P., Colombo, E., Contreras, J. L., Cortina, J., Covino, S., Da Vela, P., Dazzi, F., De Angelis, A., De Lotto, B., De Oña Wilhelmi, E., Mendez, C. Delgado, Di Pierro, F., Prester, D. Domini, Dorner, D., Doro, M., Einecke, S., Glawion, D. Eisenacher, Elsaesser, D., Fernández Barral, A., Fidalgo, D., Fonseca, M. V., Font, L., Frantzen, K., Fruck, C., Galindo, D., López, R. J. García, Garczarczyk, M., Terrats, D. Garrido, Gaug, M., Giammaria, P., Godinović, N., Muñoz, A. González, Guberman, D., Hahn, A., Hanabata, Y., Hayashida, M., Herrera, J., Hose, J., Hrupec, D., Hughes, G., Idec, W., Kodani, K., Konno, Y., Kubo, H., Kushida, J., La Barbera, A., Lelas, D., Lindfors, E., Lombardi, S., López, M., López Coto, R., López Oramas, A., Lorenz, E., Majumdar, P., Makariev, M., Mallot, K., Maneva, G., Manganaro, M., Mannheim, K., Maraschi, L., Marcote, B., Mariotti, M., Martínez, M., Mazin, D., Menzel, U., Miranda, J. M., Mirzoyan, R., Moralejo, A., Moretti, E., Nakajima, D., Neustroev, V., Niedzwiecki, A., Rosillo, M. Nieva, Nilsson, K., Nishijima, K., Noda, K., Orito, R., Overkemping, A., Paiano, S., Palacio, J., Palatiello, M., Paneque, D., Paoletti, R., Paredes, J. M., Paredes Fortuny, X., Persic, M., Poutanen, J., Moroni, P. G. Prada, Prandini, E., Puljak, I., Rhode, W., Ribó, M., Rico, J., Garcia, J. Rodriguez, Saito, T., Satalecka, K., Schultz, C., Schweizer, T., Shore, S. N., Sillanpää, A., Sitarek, J., Snidaric, I., Sobczynska, D., Stamerra, A., Steinbring, T., Strzys, M., Takalo, L., Takami, H., Tavecchio, F., Temnikov, P., Terzić, T., Tescaro, D., Teshima, M., Thaele, J., Torres, D. F., Toyama, T., Treves, A., Verguilov, V., Vovk, I., Ward, J. E., Will, M., Wu, M. H., Zanin, R., Ajello, M., Baldini, L., Barbiellini, G., Bastieri, D., González, J. Becerra, Bellazzini, R., Bissaldi, E., Blandford, R. D., Bonino, R., Bregeon, J., Bruel, P., Buson, S., Caliandro, G. A., Cameron, R. A., Caragiulo, M., Caraveo, P. A., Cavazzuti, E., Chiang, J., Chiaro, G., Ciprini, S., D'Ammando, F., De Palma, F., Desiante, R., Di Venere, L., Domínguez, A., Fusco, P., Gargano, F., Gasparrini, D., Giglietto, N., Giordano, F., Giroletti, M., Grenier, I. A., Guiriec, S., Hays, E., Hewitt, J. W., Jogler, T., Kuss, M., Larsson, S., Li, J., Li, L., Longo, Francesco, Loparco, F., Lovellette, M. N., Lubrano, P., Maldera, S., Mayer, M., Mazziotta, M. N., Mcenery, J. E., Mirabal, N., Mizuno, T., Monzani, M. E., Morselli, A., Moskalenko, I. V., Nuss, E., Ojha, R., Ohsugi, T., Omodei, N., Orlando, E., Perkins, J. S., Pesce Rollins, M., Piron, F., Pivato, G., Porter, T. A., Raino, S., Rando, R., Razzano, M., Reimer, A., Reimer, O., Sgro, C., Siskind, E. J., Spada, F., Spandre, G., Spinelli, P., Tajima, H., Takahashi, H., Thayer, J. B., Thompson, D. J., Troja, E., Wood, K. S., Balokovic, M., Berdyugin, A., Carraminana, A., Carrasco, L., Chavushyan, V., Ramazani, V. Fallah, Feige, M., Haarto, S., Haeusner, P., Hovatta, T., Kania, J., Klamt, J., Lähteenmäki, A., Leon Tavares, J., Lorey, C., Pacciani, L., Porras, A., Recillas, E., Reinthal, R., Tornikoski, M., Wolfert, D., Zottmann, N., Ahnen ML, Ansoldi S, Antonelli LA, Antoranz P, Babic A, Banerjee B, Bangale P, De Almeida UB, Barrio JA, Bednarek W, Bernardini E, Biasuzzi B, Biland A, Blanch O, Bonnefoy S, Bonnoli G, Borracci F, Bretz T, Carmona E, Carosi A, Chatterjee A, Clavero R, Colin P, Colombo E, Contreras JL, Cortina J, Covino S, Da Vela P, Dazzi F, De Angelis A, De Lotto B, Wilhelmi ED, Mendez CD, Di Pierro F, Prester DD, Dorner D, Doro M, Einecke S, Glawion DE, Elsaesser D, Fernandez-Barral A, Fidalgo D, Fonseca MV, Font L, Frantzen K, Fruck C, Galindo D, Lopez RJG, Garczarczyk M, Terrats DG, Gaug M, Giammaria P, Godinovic N, Munoz AG, Guberman D, Hahn A, Hanabata Y, Hayashida M, Herrera J, Hose J, Hrupec D, Hughes G, Idec W, Kodani K, Konno Y, Kubo H, Kushida J, La Barbera A, Lelas D, Lindfors E, Lombardi S, Lopez M, Lopez-Coto R, Lopez-Oramas A, Lorenz E, Majumdar P, Makariev M, Mallot K, Maneva G, Manganaro M, Mannheim K, Maraschi L, Marcote B, Mariotti M, Martinez M, Mazin D, Menzel U, Miranda JM, Mirzoyan R, Moralejo A, Moretti E, Nakajima D, Neustroev V, Niedzwiecki A, Rosillo M, Nilsson K, Nishijima K, Noda K, Orito R, Overkemping A, Paiano S, Palacio J, Palatiello M, Paneque D, Paoletti R, Paredes JM, Paredes-Fortuny X, Persic M, Poutanen J, Moroni PGP, Prandini E, Puljak I, Rhode W, Ribo M, Rico J, Garcia JR, Saito T, Satalecka K, Schultz C, Schweizer T, Shore SN, Sillanpaa A, Sitarek J, Snidaric I, Sobczynska D, Stamerra A, Steinbring T, Strzys M, Takalo L, Takami H, Tavecchio F, Temnikov P, Terzic T, Tescaro D, Teshima M, Thaele J, Torres DF, Toyama T, Treves A, Verguilov V, Vovk I, Ward JE, Will M, Wu MH, Zanin R, Ajello M, Baldini L, Barbiellini G, Bastieri D, Gonzalez JB, Bellazzini R, Bissaldi E, Blandford RD, Bonino R, Bregeon J, Bruel P, Buson S, Caliandro GA, Cameron RA, Caragiulo M, Caraveo PA, Cavazzuti E, Chiang J, Chiaro G, Ciprini S, DAmmando F, de Palma F, Desiante R, Di Venere L, Dominguez A, Fusco P, Gargano F, Gasparrini D, Giglietto N, Giordano F, Giroletti M, Grenier IA, Guiriec S, Hays E, Hewitt JW, Jogler T, Kuss M, Larsson S, Li J, Li L, Longo F, Loparco F, Lovellette MN, Lubrano P, Maldera S, Mayer M, Mazziotta MN, McEnery JE, Mirabal N, Mizuno T, Monzani ME, Morselli A, Moskalenko IV, Nuss E, Ojha R, Ohsugi T, Omodei N, Orlando E, Perkins JS, Pesce-Rollins M, Piron F, Pivato G, Porter TA, Raino S, Rando R, Razzano M, Reimer A, Reimer O, Sgro C, Siskind EJ, Spada F, Spandre G, Spinelli P, Tajima H, Takahashi H, Thayer JB, Thompson DJ, Troja E, Wood KS, Balokovic M, Berdyugin A, Carraminana A, Carrasco L, Chavushyan V, Ramazani VF, Feige M, Haarto S, Haeusner P, Hovatta T, Kania J, Klamt J, Lahteenmaki A, Leon-Tavares J, Lorey C, Pacciani L, Porras A, Recillas E, Reinthal R, Tornikoski M, Wolfert D, and Zottmann N
Subjects: individual (PKS 1441+25) [quasars], cosmic background radiation, Astrophysics, 7. Clean energy, Raigs gamma, Jets (Astrofísica), galaxies: active, galaxies: jets, gamma rays: galaxies, quasars: individual (PKS 1441+25), MAGIC (telescope), Space and Planetary Science, Astronomy and Astrophysics, ComputingMilieux_MISCELLANEOUS, astro-ph.HE, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, Extragalactic background light, active [galaxies], Spectral energy distribution, Electrónica, Física nuclear, Electricidad, Astrophysics - High Energy Astrophysical Phenomena, astro-ph.GA, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], cosmic background radiation – galaxies: active – galaxies: jets – gamma rays: galaxies – quasars: individual (PKS 1441+25), galaxie [gamma rays], Blazar, Quasars, Quàsars, Gamma rays, Quasar, Astrophysics - Astrophysics of Galaxies, Redshift, Galaxy, Astrophysical jets, jet [galaxies], 13. Climate action, Astrophysics of Galaxies (astro-ph.GA), Galàxies actives, Active galaxies, ddc:520, Fermi Gamma-ray Space Telescope
Abstract: The flat-spectrum radio quasar PKS 1441+25 at a redshift of z = 0.940 is detected between 40 and 250 GeV with a significance of 25.5 {\sigma} using the MAGIC telescopes. Together with the gravitationally lensed blazar QSO B0218+357 (z = 0.944), PKS 1441+25 is the most distant very high energy (VHE) blazar detected to date. The observations were triggered by an outburst in 2015 April seen at GeV energies with the Large Area Telescope on board Fermi. Multi-wavelength observations suggest a subdivision of the high state into two distinct flux states. In the band covered by MAGIC, the variability time scale is estimated to be 6.4 +/- 1.9 days. Modeling the broadband spectral energy distribution with an external Compton model, the location of the emitting region is understood as originating in the jet outside the broad line region (BLR) during the period of high activity, while being partially within the BLR during the period of low (typical) activity. The observed VHE spectrum during the highest activity is used to probe the extragalactic background light at an unprecedented distance scale for ground-based gamma-ray astronomy., Comment: Corresponding Authors: J. Becerra (josefa.becerra@nasa.gov), M. Nievas Rosillo (mnievas@ucm.es), M. Manganaro (manganaro@iac.es), F. Tavecchio (fabrizio.tavecchio@brera.inaf.it) Published in The Astrophysical Journal Letters (ApJL), 2015ApJ...815L..23A, DOI: 10.1088/2041-8205/815/2/L23
Published: 2015
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78. TeV and Multi-wavelength Observations of Mrk 421 in 2006-2008

Author: Carolin Villforth, Matthias Beilicke, P. Kaaret, A. Pichel, M. Ouellette, S. Vincent, A. Pease, R. G. Wagner, Gernot Maier, J. E. Ward, C. M. Hui, Wystan Benbow, A. Sillanpää, Michael T. Carini, S. P. Wakely, Daniel Gall, M. McCutcheon, K. Ragan, A. Konopelko, Andrei Berdyugin, S. P. Swordy, D. S. Hanna, T. C. Arlen, A. Imran, S. McArthur, V. A. Acciari, R. Dickherber, M. Kertzman, N. Karlsson, D. Steele, Karen Byrum, T. B. Humensky, P. T. Reynolds, S. Thibadeau, E. Nieppola, E. Lindfors, G. H. Sembroski, M. Schroedter, J. S. Perkins, K. Nilsson, D. Boltuch, Hugh D. Aller, G. Demet Senturk, A. C. Rovero, R. Guenette, Geza Gyuk, P. Moriarty, Nicola Galante, Stephanie Wissel, Wei Cui, Amy Furniss, M. J. Lang, M. F. Aller, Alfred Garson, A. Cesarini, David A. Williams, T. Aune, L. O. Takalo, Jamie Holder, R. A. Ong, Thomas Weisgarber, G. H. Gillanders, S. Godambe, David Kieda, L. C. Reyes, John L. Quinn, H. J. Rose, G. Finnegan, C. Duke, Robert J. Walters, E. Roache, Matthew J.A. Wood, S. M. Bradbury, V. V. Vassiliev, Abraham D. Falcone, A. C. Sadun, Lucy Fortson, E. Aliu, Henric Krawczynski, A. J.R. Weinstein, A. Varlotta, L. Ciupik, J. Sainio, A. Cannon, D. Pandel, V. Bugaev, T. Montaruli, Talvikki Hovatta, M. Baker, Anne Lähteenmäki, Kyle Cook, B. Zitzer, J. Grube, S. Smith, J. P. Finley, T. C. Weekes, J. H. Buckley, F. Krennrich, M. Pasanen, M. Theiling, A. N. Otte, Merja Tornikoski, Jeremy D. Maune, D. Barnaby, M. Pohl, and K. Lee
Subjects: individual (Mrk 421) [BL Lacertae objects], galaxies [Gamma rays], Ciencias Físicas, Astrophysics::High Energy Astrophysical Phenomena, bl-lacertae objects, FOS: Physical sciences, Multi wavelength, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, ray timing explorer, energy gamma-rays, 01 natural sciences, Spectral line, law.invention, Telescope, purl.org/becyt/ford/1 [https], Observatory, law, blazar markarian-421, 0103 physical sciences, gamma rays: galaxies, Blazar, 010303 astronomy & astrophysics, x-rays: galaxies, Cherenkov radiation, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, particle-acceleration, 010308 nuclear & particles physics, Spectral density, Astronomy and Astrophysics, purl.org/becyt/ford/1.3 [https], galaxies: jets, Redshift, Astronomía, large-area telescope, x-ray, 13. Climate action, Space and Planetary Science, correlated variability, nuclei [Galaxies], active galactic nuclei, jets [Galaxies], bl lacertae objects: individual (mrk 421), galaxies: nuclei, Astrophysics - High Energy Astrophysical Phenomena, CIENCIAS NATURALES Y EXACTAS, log-parabolic spectra
Abstract: We report on TeV gamma-ray observations of the blazar Mrk 421 (redshift of 0.031) with the VERITAS observatory and the Whipple 10m Cherenkov telescope. The excellent sensitivity of VERITAS allowed us to sample the TeV gamma-ray fluxes and energy spectra with unprecedented accuracy where Mrk 421 was detected in each of the pointings. A total of 47.3 hrs of VERITAS and 96 hrs of Whipple 10m data were acquired between January 2006 and June 2008. We present the results of a study of the TeV gamma-ray energy spectra as a function of time, and for different flux levels. On May 2nd and 3rd, 2008, bright TeV gamma-ray flares were detected with fluxes reaching the level of 10 Crab. The TeV gamma-ray data were complemented with radio, optical, and X-ray observations, with flux variability found in all bands except for the radio waveband. The combination of the RXTE and Swift X-ray data reveal spectral hardening with increasing flux levels, often correlated with an increase of the source activity in TeV gamma-rays. Contemporaneous spectral energy distributions were generated for 18 nights, each of which are reasonably described by a one-zone SSC model., Comment: 30 pages, 12 figures, accepted by ApJ
Published: 2011
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79. Veritas observations of the tev binary ls i +61° 303 during 2008-2010

Author: A. McCann, R. Dickherber, S. Thibadeau, E. Aliu, Sinéad M. Griffin, Wystan Benbow, M. P. Connolly, Gareth Hughes, R. Guenette, M. Kertzman, Gernot Maier, D. B. Saxon, N. H. Park, S. P. Wakely, Daniel Gall, J. H. Buckley, A. N. Otte, Henric Krawczynski, Jamie Holder, M. J. Lang, L. Ciupik, S. Vincent, A. J.R. Weinstein, J. S. Perkins, M. Vivier, L. C. Reyes, A. Varlotta, Reshmi Mukherjee, J. E. Ward, G. H. Sembroski, R. A. Ong, Thomas Weisgarber, M. Pohl, P. Moriarty, Nicola Galante, B. Zitzer, Geza Gyuk, Pratik Majumdar, S. LeBohec, J. Grube, Manel Errando, David A. Williams, F. Krennrich, A. D. Falcone, S. M. Bradbury, Matthew R. Orr, K. Tsurusaki, D. B. Kieda, Lucy Fortson, J. P. Finley, M. Theiling, D. Staszak, Victor A. Acciari, K. Ragan, G. Demet Senturk, C. M. Hui, Wei Cui, T. C. Weekes, Amy Furniss, A. Cannon, G. H. Gillanders, S. Godambe, H. J. Rose, H. Prokoph, V. V. Vassiliev, N. Karlsson, T. Aune, J. Ruppel, S. McArthur, V. Bugaev, Karen Byrum, G. Finnegan, A. W. Smith, C. Duke, M. Schroedter, E. Roache, A. Cesarini, G. Tešić, John L. Quinn, P. Kaaret, E. Collins-Hughes, T. B. Humensky, D. S. Hanna, T. C. Arlen, P. T. Reynolds, and Matthias Beilicke
Subjects: Astrophysics::High Energy Astrophysical Phenomena, ls-i-+61-303, FOS: Physical sciences, Proportional counter, Flux, Binary number, Astrophysics, orbital modulation, 01 natural sciences, law.invention, spectrum, Telescope, law, jet, 0103 physical sciences, MAGIC (telescope), microquasar, 010303 astronomy & astrophysics, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, high-energy emission, 010308 nuclear & particles physics, Astronomy and Astrophysics, gamma rays: general, gamma-ray emission, radio, Orbit, Crab Nebula, binaries: general, x-ray, 13. Climate action, Space and Planetary Science, x-rays: binaries, Astrophysics - High Energy Astrophysical Phenomena, Fermi Gamma-ray Space Telescope
Abstract: We present the results of observations of the TeV binary LS I +61 303 with the VERITAS telescope array between 2008 and 2010, at energies above 300 GeV. In the past, both ground-based gamma-ray telescopes VERITAS and MAGIC have reported detections of TeV emission near the apastron phases of the binary orbit. The observations presented here show no strong evidence for TeV emission during these orbital phases; however, during observations taken in late 2010, significant emission was detected from the source close to the phase of superior conjunction (much closer to periastron passage) at a 5.6 standard deviation (5.6 sigma) post-trials significance. In total, between October 2008 and December 2010 a total exposure of 64.5 hours was accumulated with VERITAS on LS I +61 303, resulting in an excess at the 3.3 sigma significance level for constant emission over the entire integrated dataset. The flux upper limits derived for emission during the previously reliably active TeV phases (i.e. close to apastron) are less than 5% of the Crab Nebula flux in the same energy range. This result stands in apparent contrast to previous observations by both MAGIC and VERITAS which detected the source during these phases at >10% of the Crab Nebula flux. During the two year span of observations, a large amount of X-ray data were also accrued on LS I +61 303 by the Swift X-ray Telescope (XRT) and the Rossi X-ray Timing Explorer Timing (RXTE) Proportional Counter Array (PCA). We find no evidence for a correlation between emission in the X-ray and TeV regimes during 20 directly overlapping observations. We also comment on data obtained contemporaneously by the Fermi Large Area Telescope (LAT)., Accepted for Publication in The Astrophysical Journal, 21 pages, 3 tables, 6 figures
Published: 2011

80. Multiwavelength Observations of the very high energy Blazar 1ES2344+514

Author: L. Ciupik, E. Aliu, R. Dickherber, P. Kaaret, R. Guenette, B. Zitzer, J. E. Ward, Gernot Maier, S. P. Swordy, A. Varlotta, S. P. Wakely, D. Boltuch, A. N. Otte, D. S. Hanna, T. C. Arlen, A. Imran, Daniel Gall, Amanda Weinstein, A. Cannon, Thomas Brian Humensky, P. Cogan, M. Schroedter, Lucy Fortson, R. A. Ong, F. Krennrich, Matthew Wood, D. Pandel, Vladimir Vassiliev, Pierre Colin, S. LeBohec, J. S. Perkins, K. Ragan, M. Theiling, Henric Krawczynski, A. Konopelko, J. P. Finley, A. W. Smith, Amy Furniss, Reshmi Mukherjee, Matthias Beilicke, J. A. Toner, T. C. Weekes, Martin Pohl, G. H. Sembroski, A. D. Falcone, P. Moriarty, John Kildea, Stephanie Wissel, David Kieda, T. Weisgarber, J. Grube, Jamie Holder, P. T. Reynolds, Rick Wagner, S. Vincent, David A. Williams, C. M. Hui, Wystan Benbow, Geza Gyuk, V. Bugaev, V. A. Acciari, P. Fortin, H. J. Rose, S. J. Fegan, D. Steele, M. J. Lang, A. Pichel, T. Aune, N. Karlsson, John L. Quinn, D. Horan, M. Kertzman, and G. H. Gillanders
Subjects: Photon, Ciencias Físicas, bl-lacertae objects, Astrophysics, 01 natural sciences, Spectral line, law.invention, Telescope, purl.org/becyt/ford/1 [https], law, veritas, 0103 physical sciences, galaxies, strong flares, individual, Blazar, 010303 astronomy & astrophysics, Physics, markarian 501, 1ES 2344+514, 010308 nuclear & particles physics, spectral variability, Astronomy and Astrophysics, purl.org/becyt/ford/1.3 [https], gamma-ray emission, Galaxy, Massless particle, bl lacertae objects: individual (ies 2344+514), radiation, Astronomía, einstein slew survey, Crab Nebula, 13. Climate action, Space and Planetary Science, correlated variability, cherenkov telescopes, BL Lacertae objects, CIENCIAS NATURALES Y EXACTAS, Flare
Abstract: Multiwavelength observations of the high-frequency-peaked blazar 1ES 2344+514 were performed from October 2007 to January 2008. The campaign represents the first contemporanous data on the object at very high energy (VHE, E > 100 GeV) gamma-ray, X-ray, and UV energies. Observations with VERITAS in VHE gamma-rays yield a strong detection of 20 sigmas with 633 excess events in a total exposure of 18.1 hours live-time. A strong VHE gamma-ray flare on December 7, 2007 is measured at F(>300 GeV) = (6.76 ± 0.62) × 10^-11 cm^-2 s^-1 , corresponding to 48% of the Crab Nebula flux. Excluding this flaring episode, nightly variability at lower fluxes is observed with a time-averaged mean of F(>300 GeV) = (1.06 ± 0.09) × 10^-11 cm^-2 s^-1 (7.6% of the Crab Nebula flux). The differential photon spectrum between 390 GeV and 8.3 TeV for the time-averaged observations excluding December 7, 2007 is well described by a power law with a photon index of 2.78 ± 0.09 (stat) ± 0.15 (syst). A slightly harder photon index of 2.43 ± 0.22stat ± 0.15syst is measured on the flaring night of December 7, 2007. Over the full period of VERITAS observations contemporaneous X-ray and UV data were taken with Swift and RXTE. Variability by a factor of ~7 is evident in the 2-10 keV flux between nightly observations. On December 8, 2007 the highest ever observed X-ray flux from 1ES 2344+514 was measured by Swift XRT at a flux of F(2-10 keV) = (6.58 ± 0.37) × 10^-11 erg cm^-2 s^-1. Evidence for a correlation between the X-ray flux and VHE gamma-ray flux on nightly time-scales is indicated with a Pearson correlation coefficient of r = 0.60 ± 0.11. Contemporaneous spectral energy distributions (SEDs) of 1ES 2344+514 are presented for two distinct flux states. A one-zone synchrotron self-Compton (SSC) model describes both SEDs using parameters consistent with previous SSC modeling of 1ES 2344+514 from non-contemporaneous observations. Fil: Acciari, V. A.. Harvard-Smithsonian Center for Astrophysics; Estados Unidos Fil: Aliu, E.. University of Delaware; Estados Unidos Fil: Arlen, T.. University of California; Estados Unidos Fil: Aune, T.. University of California; Estados Unidos Fil: Beilicke, M.. University of Washington; Estados Unidos Fil: Benbow, W.. Harvard-Smithsonian Center for Astrophysics; Estados Unidos Fil: Boltuch, D.. University of Delaware; Estados Unidos Fil: Bugaev, V.. University of Washington; Estados Unidos Fil: Cannon, A.. University College Dublin; Irlanda Fil: Ciupik, L.. Adler Planetarium and Astronomy Museum; Estados Unidos Fil: Cogan, P.. McGill University; Canadá Fil: Colin, P.. University of Utah; Estados Unidos Fil: Dickherber, R.. University of Washington; Estados Unidos Fil: Falcone, A.. University of Pennsylvania; Estados Unidos Fil: Fegan, S. J.. University of California; Estados Unidos Fil: Finley, J. P.. Purdue University; Estados Unidos Fil: Fortin, P.. Columbia University; Estados Unidos Fil: Fortson, L. F.. Adler Planetarium and Astronomy Museum; Estados Unidos Fil: Furniss, A.. University of California; Estados Unidos Fil: Gall, D.. Purdue University; Estados Unidos Fil: Gillanders, G. H.. National University of Ireland; Irlanda Fil: Grube, J.. University College Dublin; Irlanda Fil: Guenette, R.. McGill University; Canadá Fil: Gyup, G.. Adler Planetarium and Astronomy Museum; Estados Unidos Fil: Hanna, D.. McGill University; Canadá Fil: Holder, J.. University of Delaware; Estados Unidos Fil: Horan, D.. Ecole Polytechnique; Francia Fil: Hui, C. M.. University of Utah; Estados Unidos Fil: Humensky, T. B.. University Of Chicago; Estados Unidos Fil: Pichel, Ana Carolina. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentina
Published: 2011
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81. Relativistic jet activity from the tidal disruption of a star by a massive black hole

Author: D. N. Burrows, J. A. Kennea, G. Ghisellini, V. Mangano, B. Zhang, K. L. Page, M. Eracleous, P. Romano, T. Sakamoto, A. D. Falcone, J. P. Osborne, S. Campana, A. P. Beardmore, A. A. Breeveld, M. M. Chester, R. Corbet, S. Covino, J. R. Cummings, P. D'Avanzo, V. D'Elia, P. Esposito, P. A. Evans, D. Fugazza, J. M. Gelbord, K. Hiroi, S. T. Holland, K. Y. Huang, M. Im, G. Israel, Y. Jeon, Y.-B. Jeon, H. D. Jun, N. Kawai, J. H. Kim, H. A. Krimm, F. E. Marshall, null P. Mészáros, H. Negoro, N. Omodei, W.-K. Park, J. S. Perkins, M. Sugizaki, H.-I. Sung, G. Tagliaferri, E. Troja, Y. Ueda, Y. Urata, R. Usui, L. A. Antonelli, S. D. Barthelmy, G. Cusumano, P. Giommi, A. Melandri, M. Perri, J. L. Racusin, B. Sbarufatti, M. H. Siegel, and N. Gehrels
Subjects: Physics, Multidisciplinary, Active galactic nucleus, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, Milky Way, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, 01 natural sciences, Galaxy, Accretion (astrophysics), Gravitational energy, Tidal disruption event, Black hole, 13. Climate action, 0103 physical sciences, Astrophysics::Earth and Planetary Astrophysics, Blazar, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics
Abstract: Massive black holes are believed to reside at the centres of most galaxies. They can be- come detectable by accretion of matter, either continuously from a large gas reservoir or impulsively from the tidal disruption of a passing star, and conversion of the gravitational energy of the infalling matter to light. Continuous accretion drives Active Galactic Nuclei (AGN), which are known to be variable but have never been observed to turn on or off. Tidal disruption of stars by dormant massive black holes has been inferred indirectly but the on- set of a tidal disruption event has never been observed. Here we report the first discovery of the onset of a relativistic accretion-powered jet in the new extragalactic transient, Swift J164449.3+573451. The behaviour of this new source differs from both theoretical models of tidal disruption events and observations of the jet-dominated AGN known as blazars. These differences may stem from transient effects associated with the onset of a powerful jet. Such an event in the massive black hole at the centre of our Milky Way galaxy could strongly ionize the upper atmosphere of the Earth, if beamed towards us.
Published: 2011

82. Erratum: 'multi-wavelength observations of the flaring gamma-ray blazar 3c 66a in 2008 october' (2011, apj, 726, 43)

Author: Luca Baldini, Reshmi Mukherjee, Carla Buemi, I. de la Calle Perez, A. Varlotta, Wystan Benbow, Mn Mazziotta, Jamie Holder, J. P. Norris, A. Morselli, A. D. Falcone, V. Vitale, Henric Krawczynski, T. A. Porter, Takaaki Tanaka, J. Bregeon, P. Kaaret, Stefano Ciprini, David Sanchez, A. Bouvier, Keith Bechtol, J. M. Lopez, Stephen Fegan, P. D. Smith, J. Grube, A. Cannon, R. Turchetti, Manel Errando, Sang Hun Lee, Igor V. Moskalenko, D. Dumora, J. Mehault, T. Aune, J. Lande, J. E. Ward, F. Gargano, D. Pandel, T. Glanzman, P. Calcidese, S. M. Bradbury, A. Berduygin, Marco Ajello, Jun Kataoka, Olaf Reimer, Paul J. Wang, Mauro Dolci, T. Ylinen, D. Capezzali, Vladimir A. Hagen-Thorn, Seth Digel, H. Y. Hsiao, S. Buson, H. F.W. Sadrozinski, V. Bugaev, R. Bellazzini, V. A. Acciari, S. P. Swordy, J. Saino, G. Tešić, Steven Ritz, F. Piron, D. Parent, Vladimir Vassiliev, Luca Latronico, Julie McEnery, Benoit Lott, Anne Lähteenmäki, A. S. Johnson, S. Cutini, A. Konopelko, Joachim Ripken, Ekaterina Koptelova, Brian L Winer, Martin Pohl, Kari Nilsson, G. Tosti, P. L. Nolan, N. Gehrels, Uwe Bach, Corrado Trigilio, Wen Ping Chen, J. M. Casandjian, Geza Gyuk, S. Rainò, K. Ragan, A. McCann, Roger W. Romani, P. Moriarty, Gernot Maier, Karen Byrum, A. Chekhtman, Michele Fumagalli, D. Boltuch, Talvikki Hovatta, A. N. Otte, D. J. Suson, G. H. Sembroski, A. A. Moiseev, M. Pepe, M. G. Nikolashvili, A. Sievers, Ivan Agudo, D. Carosati, Deborah Dultzin, R. Dickherber, C. M. Raiteri, S. P. Wakely, D. Riquelme, Daniel Gall, Cullen H. Blake, M. Schroedter, R. A. Ong, B. Berenji, S. McArthur, Raúl Mújica, M. Razzano, T. L. Usher, Ryosuke Itoh, M. J. Lang, C. C. Cheung, M. Sorcia, D. da Rio, David S. Davis, G.L. Godfrey, J. F. Ormes, E. Do Couto E Silva, Lars Fuhrmann, E. Cavazzuti, Mark Gurwell, G. Umana, P. Spinelli, L. O. Takalo, Francesco Longo, Mar Roca-Sogorb, Claudia Cecchi, Hugh D. Aller, Atsushi Okumura, S. Thibadeau, Richard Dubois, L. A. Sigua, Elina Lindfors, J. S. Perkins, Melissa Pesce-Rollins, Markus Böttcher, A. C. Sadun, N. Karlsson, G. H. Gillanders, S. Godambe, David Hiriart, L. Ciupik, J. H. Panetta, C. Diltz, Merja Tornikoski, Tyrel J. Johnson, Tsunefumi Mizuno, Jason X. Prochaska, R. A. Cameron, Omer Celik, C. M. Hui, F. Loparco, W. N. Johnson, Charles D. Dermer, N. Galante, Diego F. Torres, E. Forné, S. LeBohec, Lucy Fortson, C. Monte, Rumen Bachev, Matthew Wood, M. Pasanen, M. McCutcheon, E. Charles, Jochen Heidt, S. Carrigan, Amy Furniss, P. Bruel, A. Tramacere, G. Demet Senturk, F. de Palma, H. Ungerechts, Stephan Wagner, G. Finnegan, A. W. Smith, Stefan Funk, O. M. Kurtanidze, M. Ziegler, José L. Gómez, Gloria Spandre, J. G. Thayer, A. Halkola, D. Hadasch, James Chiang, A. Sander, M. F. Aller, J. E. Grove, P. Roustazadeh, D. Horan, Roger Blandford, Zhenwei Yang, P. T. Reynolds, Hideaki Katagiri, E. Roache, Carmelo Sgrò, Riccardo Rando, Gianpiero Tagliaferri, E. Hays, David Kieda, Yasushi Fukazawa, David A. Williams, Amanda Weinstein, N. Vilchez, R. Guenette, Hiromitsu Takahashi, J. H. Buckley, M. Kertzman, R. Ligustri, Markus Ackermann, E. Nuss, M. S. Shaw, David Paneque, E. Aliu, P. Fortin, H. J. Rose, T. Kamae, M. Roth, M. Kuss, Erika Benítez, Emmanouil Angelakis, Jürgen Knödlseder, A. W. Borgland, Nicola Omodei, P. Fusco, F. Krennrich, Valeri M. Larionov, P. Lubrano, M. Hayashida, A. A. Abdo, E. Orlando, N. Palma, J. Ballet, A. Cesarini, D. Starr, Tatiana S. Konstantinova, G. N. Kimeridze, M. Theiling, I. Nestoras, S. Vincent, J. Dashti, Josh Bloom, Jan Conrad, S. Germani, R. Buehler, R. E. Hughes, F. Giordano, Alan P. Marscher, J. P. Finley, John L. Quinn, Luis C. Reyes, Peter F. Michelson, Marcello Giroletti, Emanuele Bonamente, A. Reimer, A. Pichel, P. Giommi, J. A. Ros, D. Steele, M. Ozaki, T. C. Weekes, D. J. Thompson, M. Hauser, Johann Cohen-Tanugi, R. Claus, A. Sillanää, M. S. Strickman, P. Beltrame, Tomaso Belloni, G. A. Caliandro, L. Guillemot, A. A. Arkharov, M. Naumann-Godo, A. P. Waite, Jeffrey D. Scargle, Marco Frailis, K. S. Wood, V. Vasileiou, D. Gasparrini, T. Ohsugi, Paolo Leto, M. Brigida, A. Brez, A. Di Paola, V. Pelassa, Nicola Giglietto, I. A. Grenier, D. S. Hanna, S. G. Jorstad, T. C. Arlen, A. Imran, L. Costamante, M. N. Lovellette, Stephanie Wissel, P. A. Caraveo, Persis S. Drell, Gudlaugur Johannesson, M. Villata, Michael Mommert, Justin Vandenbroucke, T. Weisgarber, Guido Barbiellini, Takeshi Nakamori, Thomas Brian Humensky, E. N. Kopatskaya, Matthias Beilicke, L. Tibaldo, Wei Cui, A. Makeev, M. E. Monzani, C. Favuzzi, Jodi Christiansen, J. B. Thayer, J. A. Zensus, S. Murgia, Denis Bastieri, and Sylvain Guiriec
Subjects: Physics, Space and Planetary Science, Gamma ray, Astronomy, Astronomy and Astrophysics, Multi wavelength, Astrophysics, Blazar
Published: 2011

83. Discovery of TeV Gamma Ray Emission from Tycho's Supernova Remnant

Author: S. McArthur, D. S. Hanna, P. Majumdar, J. E. Ward, V. A. Acciari, J. P. Finley, Philip Kaaret, A. S. Madhavan, Wystan Benbow, V. Bugaev, M. Kertzman, Gernot Maier, J. H. Buckley, T. C. Weekes, G. Tešić, M. J. Lang, E. Collins-Hughes, J. S. Perkins, S. P. Wakely, R. Dickherber, A. Cesarini, T. Aune, D. Gall, M. Beilicke, E. Aliu, S. Thibadeau, John L. Quinn, Henric Krawczynski, Karen Byrum, Geza Gyuk, Jamie Holder, G. Demet Senturk, H. J. Rose, A. Furniss, R. A. Ong, A. Varlotta, J. Grube, A. N. Otte, Frank Krennrich, M. Schroedter, Manel Errando, R. Guenette, M. Vivier, Reshmi Mukherjee, S. M. Bradbury, L. Ciupik, Vladimir Vassiliev, A. Cannon, C. M. Hui, S. Griffin, Stephan LeBohec, N. Karlsson, K. Tsurusaki, N. Galante, D. B. Saxon, David Kieda, David A. Williams, M. Theiling, N. H. Park, Patrick Slane, G. Finnegan, A. W. Smith, P. T. Reynolds, C. Duke, Lucy Fortson, Amanda Weinstein, Matthew Wood, G. H. Gillanders, P. Moriarty, S. Godambe, Dirk Pandel, M. Orr, Martin Pohl, K. Ragan, B. Zitzer, E. Roache, Thomas Brian Humensky, John P. Hughes, L. C. Reyes, A. McCann, Wei Cui, T. Weisgarber, S. Vincent, G. H. Sembroski, and T. C. Arlen
Subjects: catalog, Photon, shock acceleration, Point source, chandra, Astrophysics::High Energy Astrophysical Phenomena, Hadron, FOS: Physical sciences, Astrophysics, Type (model theory), 01 natural sciences, spectrum, expansion, 0103 physical sciences, Supernova remnant, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, hess, 010308 nuclear & particles physics, turbulence, Gamma ray, Institut für Physik und Astronomie, Astronomy and Astrophysics, gamma rays: general, astronomy, galactic plane survey, Crab Nebula, Space and Planetary Science, ddc:520, High Energy Physics::Experiment, ism: individual objects (g120.1+01.4, tycho=ver j0025+641), constraints, Astrophysics - High Energy Astrophysical Phenomena, Energy (signal processing)
Abstract: We report the discovery of TeV gamma-ray emission from the Type Ia supernova remnant (SNR) G120.1+1.4, known as Tycho's supernova remnant. Observations performed in the period 2008-2010 with the VERITAS ground-based gamma-ray observatory reveal weak emission coming from the direction of the remnant, compatible with a point source located at $00^{\rm h} \ 25^{\rm m} \ 27.0^{\rm s},\ +64^{\circ} \ 10^{\prime} \ 50^{\prime\prime}$ (J2000). The TeV photon spectrum measured by VERITAS can be described with a power-law $dN/dE = C(E/3.42\;\textrm{TeV})^{-\Gamma}$ with $\Gamma = 1.95 \pm 0.51_{stat} \pm 0.30_{sys}$ and $C = (1.55 \pm 0.43_{stat} \pm 0.47_{sys}) \times 10^{-14}$ cm$^{-2}$s$^{-1}$TeV$^{-1}$. The integral flux above 1 TeV corresponds to $\sim 0.9%$ percent of the steady Crab Nebula emission above the same energy, making it one of the weakest sources yet detected in TeV gamma rays. We present both leptonic and hadronic models which can describe the data. The lowest magnetic field allowed in these models is $\sim 80 \mu$G, which may be interpreted as evidence for magnetic field amplification., Comment: 6 pages, 3 figures. Accepted in ApJL
Published: 2011
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84. Veritas observations of unusual extragalactic transient swift J164449.3+573451

Author: Philip Kaaret, A. S. Madhavan, Wystan Benbow, D. Hanna, N. Karlsson, Gernot Maier, A. McCann, A. N. Otte, Frank Krennrich, Wei Cui, G. Tešić, S. P. Wakely, M. P. Connolly, A. Pichel, Geza Gyuk, H. Prokoph, C. M. Hui, E. Roache, D. Gall, M. Vivier, E. Collins-Hughes, S. Thibadeau, Jamie Holder, T. B. Humensky, Martin Pohl, Amanda Weinstein, P. T. Reynolds, A. Bouvier, David Kieda, M. Schroedter, R. Mukherjee, M. Theiling, J. E. Ward, J. H. Buckley, D. B. Saxon, Luis C. Reyes, S. Vincent, N. H. Park, G. H. Sembroski, T. Aune, R. A. Ong, L. Ciupik, A. Cesarini, T. Arlen, Markus Böttcher, K. Tsurusaki, Lucy Fortson, R. Dickherber, A. Furniss, John L. Quinn, David A. Williams, A. Varlotta, K. Ragan, M. Kertzman, P. Majumdar, G. H. Gillanders, H. J. Rose, A. D. Falcone, C. Skole, J. S. Perkins, S. Godambe, S. McArthur, V. Bugaev, M. Orr, G. Hughes, S. M. Bradbury, A. Cannon, J. Ruppel, J. Grube, Manel Errando, J. Tyler, N. Galante, T. Weisgarber, A. W. Smith, S. Griffin, H. Huan, Henric Krawczynski, J. P. Finley, P. Moriarty, M. Beilicke, E. Aliu, and D. Staszak
Subjects: Swift, Ciencias Físicas, Astrophysics::High Energy Astrophysical Phenomena, galaxies: active, Flux, FOS: Physical sciences, Astrophysics, 7. Clean energy, 01 natural sciences, purl.org/becyt/ford/1 [https], Observatory, gamma-ray astronomy, gamma rays: galaxies, 0103 physical sciences, 010303 astronomy & astrophysics, computer.programming_language, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), accretion, accretion disks, 010308 nuclear & particles physics, Institut für Physik und Astronomie, Astronomy and Astrophysics, purl.org/becyt/ford/1.3 [https], radiation mechanisms: non-thermal, non-thermal [radiation mechanisms], Astronomía, Space and Planetary Science, active [galaxies], galaxies [gamma rays], cherenkov telescopes, Transient (oscillation), light, Astrophysics - High Energy Astrophysical Phenomena, computer, CIENCIAS NATURALES Y EXACTAS
Abstract: We report on very high energy (E > 100 GeV) gamma-ray observations of Swift J164449.3+573451, an unusual transient object first detected by the Swift Observatory and later detected by multiple radio, optical, and X-ray observatories.A total exposure of 28 hr was obtained on Swift J164449.3+573451 with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) during 2011 March 28-April 15. We do not detect the source and place a differential upper limit on the emission at 500 GeV during these observations of 1.4 x 10^-12 erg cm^-2 s^-1 (99 % confidence level). We also present time-resolved upper limits and use a flux limit averaged over the X-ray flaring period to constrain various emission scenarios that can accommodate both the radio-through-X-ray emission detected from the source and the lack of detection by VERITAS. Fil: Aliu, E.. Columbia University; Estados Unidos Fil: Arlen, T.. University of California; Estados Unidos Fil: Aune, T.. University of California; Estados Unidos Fil: Beilicke, M.. University of Washington; Estados Unidos Fil: Benbow, W.. Harvard-Smithsonian Center for Astrophysics; Estados Unidos Fil: Bottcher, M.. Ohio University; Estados Unidos Fil: Bouvier, A.. University of California; Estados Unidos Fil: Bradbury, S. M.. University of Leeds; Reino Unido Fil: Buckley, J. H.. University of Washington; Estados Unidos Fil: Bugaev, V.. University of Washington; Estados Unidos Fil: Cannon, A.. University College Dublin; Irlanda Fil: Cesarini, A.. National University of Ireland Galway; Irlanda Fil: Ciupik, L.. Adler Planetarium and Astronomy Museum; Estados Unidos Fil: Collins Hughes, E.. University College Dublin; Irlanda Fil: Connolly, M. P.. National University of Ireland Galway; Irlanda Fil: Cui, W.. Purdue University; Estados Unidos Fil: Dickherber, R.. University of Washington; Estados Unidos Fil: Errando, M.. Columbia University; Estados Unidos Fil: Falcone, A.. University of Pennsylvania; Estados Unidos Fil: Finley, J. P.. Purdue University; Estados Unidos Fil: Fortson, L.. University Of Minnesota; Estados Unidos Fil: Furniss, A.. University of California; Estados Unidos Fil: Galante, N.. Harvard-Smithsonian Center for Astrophysics; Estados Unidos Fil: Gall, D.. University of Iowa; Estados Unidos Fil: Gillanders, G. H.. National University of Ireland Galway; Irlanda Fil: Godambe, S.. University of Utah; Estados Unidos Fil: Griffin, S.. McGill University; Canadá Fil: Grube, J.. Adler Planetarium and Astronomy Museum; Estados Unidos Fil: Gyuk, G.. Adler Planetarium and Astronomy Museum; Estados Unidos Fil: Pichel, Ana Carolina. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentina Fil: The Veritas Collaboration.
Published: 2011
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85. Multiwavelength observations of the previously unidentified blazar RX J0648.7+1516

Author: A. Cesarini, John L. Quinn, Stefano Ciprini, D. B. Saxon, N. Karlsson, N. H. Park, D. Staszak, K. Ragan, A. McCann, Geza Gyuk, Pratik Majumdar, Gernot Maier, B. Zitzer, Sinéad M. Griffin, S. P. Wakely, Daniel Gall, R. A. Ong, S. M. Bradbury, Lucy Fortson, E. Aliu, Manel Errando, Gareth Hughes, M. Kertzman, Markus Böttcher, V. V. Vassiliev, P. Moriarty, Nicola Galante, J. Tyler, Jamie Holder, L. Ciupik, Wystan Benbow, R. Dickherber, J. Grube, J. H. Buckley, G. Tešić, David Paneque, S. Thibadeau, L. C. Reyes, Henric Krawczynski, A. J.R. Weinstein, M. P. Connolly, A. Varlotta, C. M. Hui, F. Krennrich, Matthias Beilicke, K. Tsurusaki, David A. Williams, Jason X. Prochaska, Amy Furniss, Martin Pohl, G. Finnegan, A. W. Smith, M. Theiling, G. H. Gillanders, C. Duke, G. H. Sembroski, J. Ruppel, A. Bouvier, T. C. Weekes, E. Roache, S. Godambe, H. Huan, A. N. Otte, T. J. N. Nelson, David Kieda, Reshmi Mukherjee, D. S. Hanna, A. Cannon, Wei Cui, Michele Fumagalli, G. Decerprit, C. Skole, J. S. Perkins, H. Prokoph, P. T. Reynolds, Matthew R. Orr, P. Kaaret, A. Pichel, B. Hivick, Q. Feng, T. B. Humensky, T. Aune, H. J. Rose, A. D. Falcone, Kyle F. Kaplan, S. McArthur, V. Bugaev, Aliu, E, Aune, T, Beilicke, M, Benbow, W, Bottcher, M, Bouvier, A, Bradbury, S, Buckley, J, Bugaev, V, Cannon, A, Cesarini, A, Ciupik, L, Connolly, M, Cui, W, Decerprit, G, Dickherber, R, Duke, C, Errando, M, Falcone, A, Feng, Q, Finnegan, G, Fortson, L, Furniss, A, Galante, N, Gall, D, Gillanders, G, Godambe, S, Griffin, S, Grube, J, Gyuk, G, Hanna, D, Hivick, B, Holder, J, Huan, H, Hughes, G, Hui, C, Humensky, T, Kaaret, P, Karlsson, N, Kertzman, M, Kieda, D, Krawczynski, H, Krennrich, F, Maier, G, Majumdar, P, Mcarthur, S, Mccann, A, Moriarty, P, Mukherjee, R, Nelson, T, Ong, R, Orr, M, Otte, A, Park, N, Perkins, J, Pichel, A, Pohl, M, Prokoph, H, Quinn, J, Ragan, K, Reyes, L, Reynolds, P, Roache, E, Rose, H, Ruppel, J, Saxon, D, Sembroski, G, Skole, C, Smith, A, Staszak, D, Teisic, G, Theiling, M, Thibadeau, S, Tsurusaki, K, Tyler, J, Varlotta, A, Vassiliev, V, Wakely, S, Weekes, T, Weinstein, A, Williams, D, Zitzer, B, Ciprini, S, Fumagalli, M, Kaplan, K, Paneque, D, and Prochaska, J
Subjects: Astrophysics::High Energy Astrophysical Phenomena, Ciencias Físicas, bl-lacertae objects, Flux, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Type (model theory), 01 natural sciences, 7. Clean energy, law.invention, Telescope, purl.org/becyt/ford/1 [https], Observatory, law, veritas, 0103 physical sciences, bl lacertae objects: individual (rx j0648.7+1516, 1fgl j0648.8+1516, ver j0648+152), gamma rays: galaxies, all-sky survey, individual 21 (RXJ0648.7+1516, 1FGL J0648.8+1516, VERJ0648+152) [BL Lacertae 20 objects], gamma rays: galaxie, Blazar, 010303 astronomy & astrophysics, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), particle-acceleration, 010308 nuclear & particles physics, ray, Institut für Physik und Astronomie, Astronomy and Astrophysics, source catalog, purl.org/becyt/ford/1.3 [https], Redshift, Astronomía, large-area telescope, mission, 13. Climate action, Space and Planetary Science, galaxies [gamma rays], Astrophysics - High Energy Astrophysical Phenomena, CIENCIAS NATURALES Y EXACTAS, BL Lac object, Fermi Gamma-ray Space Telescope
Abstract: We report on the VERITAS discovery of very-high-energy (VHE) gamma-ray emission above 200 GeV from the high-frequency-peaked BL Lac object RXJ0648.7+1516 (GBJ0648+1516), associated with 1FGL J0648.8+1516. The photon spectrum above 200 GeV is fit by a power law dN/dE = F0(E/E0)-Gamma with a photon index of 4.4 ± 0.8stat ± 0.3syst and a flux normalization F0 of (2.3± 0.5stat ±1.2sys)×10^-11 TeV^-1cm^-2s^-1 with E0 = 300 GeV. No VHE variability is detected during VERITAS observations of RXJ0648.7+1516 between 2010 March 4 and April 15. Following the VHE discovery, the optical identification and spectroscopic redshift were obtained using the Shane 3–m Telescope at the Lick Observatory, showing the unidentified object to be a BL Lac type with a redshift of z = 0.179. Broadband multiwavelength observations contemporaneous with the VERITAS exposure period can be used to sub-classify the blazar as a high-frequency-peaked BL Lac (HBL) object, including data from the MDM observatory, Swift -UVOT and XRT, and continuous monitoring at photon energies above 1 GeV from the Fermi Large Area Telescope (LAT). We find that in the absence of undetected, high-energy rapid variability, the one-zone synchrotron self-Compton model (SSC) overproduces the high-energy gamma-ray emission measured by the Fermi -LAT over 2.3 years. The SED can be parameterized satisfactorily with an external-Compton or lepto-hadronic model, which have two and six additional free parameters, respectively, compared to the one-zone SSC model. Fil: Aliu, E.. Columbia University; Estados Unidos Fil: Aune, T.. University of California; Estados Unidos Fil: Beilicke, M.. University of Washington; Estados Unidos Fil: Benbow, W.. Harvard-Smithsonian Center for Astrophysics; Estados Unidos Fil: Bottcher, M.. Ohio University; Estados Unidos Fil: Bouvier, A.. University of California; Estados Unidos Fil: Bradbury, S. M.. University of Leeds; Reino Unido Fil: Buckley, J. H.. Washington University; Estados Unidos Fil: Bugaev, V.. Washington University; Estados Unidos Fil: Cannon, A.. University College Dublin,; Irlanda Fil: Cesarini, A.. National University of Ireland Galway; Irlanda Fil: Ciupik, L.. Adler Planetarium and Astronomy; Estados Unidos Fil: Connolly, M. P.. National University of Ireland Galway; Irlanda Fil: Cui, W.. Purdue University; Estados Unidos Fil: Decerprit, D.. Desy; Alemania Fil: Dickherber, R.. Washington University; Estados Unidos Fil: Duke, C.. Grinnell College; Estados Unidos Fil: Errando, M.. Columbia University; Estados Unidos Fil: Falcone, A.. Pennsylvania State University; Estados Unidos Fil: Feng, Q.. Purdue University; Estados Unidos Fil: Finnegan, G.. University of Utah; Estados Unidos Fil: Fortson, L.. University of Minnesota; Estados Unidos Fil: Furniss, A.. University of California; Estados Unidos Fil: Galante, N.. Harvard-Smithsonian Center for Astrophysics; Estados Unidos Fil: Gall, D.. University of Iowa; Estados Unidos Fil: Gillanders, G. H.. National University of Ireland Galway; Irlanda Fil: Godambe, S.. University of Utah; Estados Unidos Fil: Griffin, S.. McGill University; Canadá Fil: Grube, J.. Adler Planetarium and Astronomy Museum; Estados Unidos Fil: Pichel, Ana Carolina. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentina Fil: The Veritas Collaboration.
Published: 2011

86. Spreading deserts or spatially confined environmental impacts? land degradation and cattle ranching in the kalahari desert of botswana

Author: David S.G. Thomas and J. S. Perkins
Subjects: Land use, business.industry, Agroforestry, Ecology, media_common.quotation_subject, Soil Science, Development, Geography, Desertification, Soil retrogression and degradation, Extensive farming, Grazing, Land degradation, Environmental Chemistry, Livestock, business, Environmental degradation, General Environmental Science, media_common
Abstract: The Kalahari Desert of Botswana is being increasingly used for livestock production, particularly through the establishment of ranches dependent on borehole water supplies. Reports of the environmental impacts of land use practices in such drylands are conflicting, with livestock systems supplied by boreholes and wells being regarded in some studies as centres for the spread of desertification and in others as having environmental impacts that are overridden by the effects of natural climatic variability. the results of an environmental study focused on a block of borehole ranches established in the eastern Kalahari as part of Botswana's Tribal Grazing Lands Policy dating from the 1970s are reported. the investigations concentrated on ecological, soil chemistry and soil erosion impacts on the study ranches. Although important changes in the ecology and soil nutrient status of the ranches are identified, their contribution to environmental degradation must be viewed in terms of stocking levels, The radial nature of range usage, giving rise to marked spatial variations in impact, and natural climatic variability. Changes are not solely detrimental, but long-term monitoring, especially in relation to climatic fluctuations, needs to be undertaken to fully establish the dynamic interactions of variables.
Published: 1993
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87. Erratum: 'veritas observations of a very high energy γ-ray flare from the blazar 3c 66a' (2009, apj, 693, l104)

Author: A. Varlotta, John Kildea, M. J. Lang, M. Beilicke, Wystan Benbow, Henric Krawczynski, R. G. Wagner, J. P. Finley, Lucy Fortson, Matthew Wood, A. Cannon, Martin Pohl, G. H. Sembroski, D. Pandel, Yousaf M. Butt, J. A. Toner, N. Karlsson, M. McCutcheon, A. McCann, C. M. Hui, T. C. Weekes, R. Dickherber, P. Moriarty, E. Hays, J. Grube, L. Ciupik, J. S. Perkins, Thomas Brian Humensky, V. Bugaev, V. A. Acciari, Stephanie Wissel, Geza Gyuk, David A. Williams, E. Aliu, Y. C. Chow, Reshmi Mukherjee, D. Horan, Amanda Weinstein, David Kieda, R. Guenette, M. K. Daniel, R. A. Ong, M. Kertzman, D. Petry, B. Zitzer, Gernot Maier, K. Ragan, S. M. Bradbury, P. Fortin, H. J. Rose, A. Konopelko, Markus Böttcher, S. LeBohec, P. Kaaret, S. P. Wakely, G. H. Gillanders, S. Godambe, S. P. Swordy, S. J. Fegan, Daniel Gall, O. Celik, D. Steele, F. Pizlo, Karen Byrum, D. S. Hanna, T. C. Arlen, M. Schroedter, A. Imran, Jamie Holder, J. E. Ward, Wei Cui, A. Cesarini, A. N. Otte, John L. Quinn, A. W. Smith, J. Millis, K. G. Gibbs, E. Roache, A. D. Falcone, P. Cogan, Luis C. Reyes, Vladimir Vassiliev, Amy Furniss, Tulun Ergin, F. Krennrich, M. Theiling, J. H. Buckley, P. T. Reynolds, and T. Nagai
Subjects: Physics, High energy, Space and Planetary Science, law, Astronomy, Astronomy and Astrophysics, Astrophysics, Blazar, Flare, law.invention
Published: 2010

88. Discovery of very high energy γ-ray emission from the snr g54.1+0.3

Author: A. McCann, R. A. Ong, Thomas Weisgarber, S. LeBohec, Gernot Maier, M. Beilicke, N. Karlsson, S. P. Wakely, Daniel Gall, S. M. Bradbury, G. Demet Senturk, D. Pandel, R. Dickherber, S. Thibadeau, T. B. Humensky, D. Boltuch, D. Steele, J. E. Ward, T. Aune, Geza Gyuk, B. Zitzer, S. McArthur, J. Grube, R. Guenette, L. Ciupik, V. A. Acciari, Jamie Holder, C. M. Hui, A. Furniss, E. Aliu, H. Krawczynski, G. H. Gillanders, F. Krennrich, S. Godambe, M. McCutcheon, A. Cesarini, P. Kaaret, S. P. Swordy, John L. Quinn, G. H. Sembroski, M. Bautista, R. Muhkerjee, K. Ragan, Y. Butt, G. Těsić, M. Theiling, A. Konopelko, Wystan Benbow, L. C. Reyes, M. Schroedter, Stephanie Wissel, S. Vincent, E. Roache, H. J. Rose, T. Arlen, Patrick Slane, J. H. Buckley, M. Kertzman, A. N. Otte, Matthew J.A. Wood, J. P. Finley, T. C. Weekes, M. J. Lang, Eric V. Gotthelf, David Kieda, A. Imran, David A. Williams, G. Finnegan, A. W. Smith, C. Duke, V. V. Vassiliev, P. Moriarty, Nicola Galante, D. S. Hanna, V. Bugaev, J. S. Perkins, Wei Cui, A. J.R. Weinstein, K. Byrum, P. T. Reynolds, Lucy Fortson, and Martin Pohl
Subjects: supernova remnant g54.1+0.3, catalog, Photon, Astrophysics::High Energy Astrophysical Phenomena, Flux, Astrophysics, pulsar wind nebulae, telescope, 01 natural sciences, g0.9+0.1, Luminosity, Pulsar, Observatory, veritas, 0103 physical sciences, crab-nebula, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, search, 010308 nuclear & particles physics, Resolution (electron density), Gamma ray, Astronomy and Astrophysics, gamma rays: general, pulsars: individual (j1930+1852, j1928+1746), astronomy, Crab Nebula, 13. Climate action, Space and Planetary Science, ism: supernova remnants, ddc:520, High Energy Physics::Experiment
Abstract: We report the discovery of very high energy (VHE) gamma-ray emission from the direction of the SNR G54.1+ 0.3 using the VERITAS ground-based gamma-ray observatory. The TeV signal has an overall significance of 6.8s and appears pointlike given the resolution of the instrument. The integral flux above 1 TeV is 2.5% of the Crab Nebula flux and significant emission is measured between 250 GeV and 4 TeV, well described by a power-law energy spectrum dN/dE similar to E(-Gamma) with a photon index Gamma = 2.39 +/- 0.23(stat) +/- 0.30sys. We find no evidence of time variability among observations spanning almost two years. Based on the location, the morphology, the measured spectrum, the lack of variability, and a comparison with similar systems previously detected in the TeV band, the most likely counterpart of this new VHE gamma-ray source is the pulsar wind nebula (PWN) in the SNR G54.1+0.3. The measured X-ray to VHE gamma-ray luminosity ratio is the lowest among all the nebulae supposedly driven by young rotation-powered pulsars, which could indicate a particle-dominated PWN.
Published: 2010
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89. Veritas upper limit on the very high energy emission from the radio galaxy NGC 1275

Author: V. A. Acciari, E. Aliu, T. Arlen, T. Aune, M. Bautista, M. Beilicke, W. Benbow, D. Boltuch, S. M. Bradbury, J. H. Buckley, V. Bugaev, K. Byrum, A. Cannon, O. Celik, A. Cesarini, L. Ciupik, P. Cogan, W. Cui, R. Dickherber, C. Duke, S. J. Fegan, J. P. Finley, P. Fortin, L. Fortson, A. Furniss, N. Galante, D. Gall, K. Gibbs, G. H. Gillanders, S. Godambe, J. Grube, R. Guenette, G. Gyuk, D. Hanna, J. Holder, D. Horan, C. M. Hui, T. B. Humensky, A. Imran, P. Kaaret, N. Karlsson, M. Kertzman, D. Kieda, A. Konopelko, H. Krawczynski, F. Krennrich, M. J. Lang, S. LeBohec, G. Maier, A. McCann, M. McCutcheon, J. Millis, P. Moriarty, R. Mukherjee, R. A. Ong, A. N. Otte, D. Pandel, J. S. Perkins, M. Pohl, J. Quinn, K. Ragan, P. T. Reynolds, E. Roache, H. J. Rose, M. Schroedter, G. H. Sembroski, A. W. Smith, D. Steele, S. P. Swordy, M. Theiling, J. A. Toner, A. Varlotta, V. V. Vassiliev, S. Vincent, R. G. Wagner, S. P. Wakely, J. E. Ward, T. C. Weekes, A. Weinstein, T. Weisgarber, D. A. Williams, S. Wissel, M. Wood, B. Zitzer, J. Kataoka, E. Cavazzuti, C. C. Cheung, B. Lott, D. J. Thompson, G. Tosti, Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), and Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: jets, [PHYS.ASTR.HE]Physics [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], Active galactic nucleus, Radio galaxy, Perseus A), Astrophysics::High Energy Astrophysical Phenomena, Flux, proton blazar, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, law.invention, galaxies: individual: NGC 1275 3C 84 Perseus A, Telescope, atmospheric cherenkov telescopes, Spitzer Space Telescope, law, 0103 physical sciences, 3C 84, Limit (mathematics), galaxies: Seyfert, gamma rays: observations, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, parameters, 010308 nuclear & particles physics, [SDU.ASTR.HE]Sciences of the Universe [physics]/Astrophysics [astro-ph]/High Energy Astrophysical Phenomena [astro-ph.HE], galaxies: individual (NGC 1275, Astronomy and Astrophysics, gamma-ray emission, galaxies: individual (ngc 1275, 3c 84, perseus a), radiation, Crab Nebula, Space and Planetary Science, markarian-501, active galactic nuclei, peaked bl-lacertae, discovery, Fermi Gamma-ray Space Telescope
Abstract: The recent detection by the Fermi gamma-ray space telescope of high-energy gamma-rays from the radio galaxy NGC 1275 makes the observation of the very high energy (VHE: E > 100 GeV) part of its broadband spectrum particularly interesting, especially for the understanding of active galactic nuclei (AGN) with misaligned multi-structured jets. The radio galaxy NGC 1275 was recently observed by VERITAS at energies above 100 GeV for about 8 hours. No VHE gamma-ray emission was detected by VERITAS from NGC 1275. A 99% confidence level upper limit of 2.1% of the Crab Nebula flux level is obtained at the decorrelation energy of approximately 340 GeV, corresponding to 19% of the power-law extrapolation of the Fermi Large Area Telescope (LAT) result.
Published: 2009
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90. A connection between star formation activity and cosmic rays in the starburst galaxy M82

Author: V. A. Acciari, M. J. Lang, A. Cesarini, Pierre Colin, John L. Quinn, L. C. Reyes, K. G. Gibbs, R. Guenette, J. E. Ward, A. N. Otte, Frank Krennrich, A. McCann, S. P. Swordy, R. Dickherber, T. Aune, Karen Byrum, T. Weisgarber, S. Thibadeau, M. Theiling, G. H. Gillanders, S. Godambe, Philip Kaaret, M. Schroedter, D. S. Hanna, T. C. Arlen, A. Imran, S. M. Bradbury, Wystan Benbow, J. Millis, Reshmi Mukherjee, F. Pizlo, S. J. Fegan, M. Beilicke, John Kildea, D. Steele, N. Karlsson, M. McCutcheon, David A. Williams, P. Moriarty, Gernot Maier, A. Cannon, Stephanie Wissel, D. Pandel, S. P. Wakely, Daniel Gall, D. Boltuch, J. H. Buckley, N. Galante, R. A. Ong, S. LeBohec, P. Cogan, G. Finnegan, A. W. Smith, David Kieda, Vladimir Vassiliev, C. Duke, Wei Cui, E. Roache, Thomas Brian Humensky, Jamie Holder, Lucy Fortson, Matthew Wood, V. Bugaev, S. McArthur, L. Ciupik, Amy Furniss, Geza Gyuk, E. Aliu, A. Varlotta, B. Zitzer, J. S. Perkins, K. Ragan, A. Konopelko, Martin Pohl, G. H. Sembroski, Henric Krawczynski, T. Nagai, R. G. Wagner, C. M. Hui, D. Horan, M. Kertzman, J. Grube, J. P. Finley, T. C. Weekes, P. T. Reynolds, S. Vincent, Y. C. Chow, O. Celik, Manuel A. Bautista, Amanda Weinstein, P. Fortin, and H. J. Rose
Subjects: Physics, High rate, Cosmology and Nongalactic Astrophysics (astro-ph.CO), Multidisciplinary, 010308 nuclear & particles physics, Star formation, Protogalaxy, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Astronomy, Cosmic ray, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Radiation, 01 natural sciences, Galaxy, Supernova, Stars, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: Although Galactic cosmic rays (protons and nuclei) are widely believed to be dominantly accelerated by the winds and supernovae of massive stars, definitive evidence of this origin remains elusive nearly a century after their discovery [1]. The active regions of starburst galaxies have exceptionally high rates of star formation, and their large size, more than 50 times the diameter of similar Galactic regions, uniquely enables reliable calorimetric measurements of their potentially high cosmic-ray density [2]. The cosmic rays produced in the formation, life, and death of their massive stars are expected to eventually produce diffuse gamma-ray emission via their interactions with interstellar gas and radiation. M 82, the prototype small starburst galaxy, is predicted to be the brightest starburst galaxy in gamma rays [3, 4]. Here we report the detection of >700 GeV gamma rays from M 82. From these data we determine a cosmic-ray density of 250 eV cm-3 in the starburst core of M 82, or about 500 times the average Galactic density. This result strongly supports that cosmic-ray acceleration is tied to star formation activity, and that supernovae and massive-star winds are the dominant accelerators., 18 pages, 4 figures; published in Nature; Version is prior to Nature's in-house style editing (differences are minimal)
Published: 2009

91. VERITAS OBSERVATIONS OF THE BL LAC OBJECT 1ES 1218+304

Author: John Kildea, P. Kaaret, T. Nagai, Rick Wagner, L. C. Reyes, Y. C. K. Chow, O. Celik, M. J. Lang, Tulun Ergin, V. Bugaev, John Toner, A. McCann, D. Horan, Geza Gyuk, J. E. Ward, Amy Furniss, R. Guenette, Martin Pohl, S. J. Fegan, D. Steele, A. Konopelko, D. S. Hanna, D. Pandel, V. A. Acciari, Pierre Colin, Wystan Benbow, A. W. Smith, Jacek Niemiec, J. P. Finley, M. K. Daniel, P. T. Reynolds, Gernot Maier, T. C. Weekes, P. Cogan, S. P. Wakely, R. Mukherjee, S. P. Swordy, G. H. Gillanders, H. J. Rose, M. Schroedter, R. J. White, Lucy Fortson, Matthew Wood, T. B. Humensky, Wei Cui, Abraham D. Falcone, E. Hays, L. Valcarcel, A. Cesarini, Stephanie Wissel, John L. Quinn, Karen Byrum, N. Karlsson, C. M. Hui, David Kieda, V. V. Vassiliev, M. McCutcheon, P. Moriarty, M. Kertzman, M. Beilicke, J. S. Perkins, T. Arlen, P. Fortin, F. Krennrich, Henric Krawczynski, A. Imran, J. H. Buckley, David A. Williams, K. Ragan, Y. Butt, J. Grube, Jamie Holder, L. Ciupik, E. Aliu, B. Zitzer, S. M. Bradbury, A. Weinstein, G. H. Sembroski, R. A. Ong, and S. LeBohec
Subjects: extragalactic background light, Active galactic nucleus, radiation-fields, spectra, galaxies: active, Astrophysics, telescope, energy gamma-rays, emission, MAGIC (telescope), Blazar, Physics, bl lacertae objects: individual (1es 1218+304), tev blazars, hess, Astronomy, Astronomy and Astrophysics, Light curve, Redshift, Crab Nebula, x-ray, Extragalactic background light, Space and Planetary Science, gamma rays: observations, discovery, BL Lac object
Abstract: The VERITAS collaboration reports the detection of very-high-energy gamma-ray emission from the high-frequency-peaked BL Lac object 1ES 1218+304 located at a redshift of z = 0.182. A gamma-ray signal was detected with a statistical significance of 10.4 standard deviations (10.4 sigma) for the observations taken during the first three months of 2007, confirming the discovery of this object made by the MAGIC collaboration. The photon spectrum between similar to 160 GeV and similar to 1.8 TeV is well described by a power law with an index of Gamma = 3.08 +/- 0.34(stat) +/- 0.2(sys). The integral flux is Phi (E > 200 GeV) = (12.2 +/- 2.6) x 10(-12) cm(-2) s(-1), which corresponds to similar to 6% of that of the Crab Nebula. The light curve does not show any evidence for very high energy flux variability. Using lower limits on the density of the extragalactic background light in the near to mid-infrared, we are able to limit the range of intrinsic energy spectra for 1ES 1218+304. We show that the intrinsic photon spectrum has an index that is harder than Gamma = 2.32 +/- 0.37(stat). When including constraints from the spectra of 1ES 1101-232 and 1ES 0229+200, the spectrum of 1ES 1218+ 304 is likely to be harder than Gamma = 1.86 +/- 0.37(stat).
Published: 2009

92. Multiwavelength observations of markarian 421 in 2005-2006

Author: D. Horan, V. A. Acciari, S. M. Bradbury, J. H. Buckley, V. Bugaev, K. L. Byrum, A. Cannon, O. Celik, A. Cesarini, Y. C. K. Chow, L. Ciupik, P. Cogan, A. D. Falcone, S. J. Fegan, J. P. Finley, P. Fortin, L. F. Fortson, D. Gall, G. H. Gillanders, J. Grube, G. Gyuk, D. Hanna, E. Hays, M. Kertzman, J. Kildea, A. Konopelko, H. Krawczynski, F. Krennrich, M. J. Lang, K. Lee, P. Moriarty, T. Nagai, J. Niemiec, R. A. Ong, J. S. Perkins, M. Pohl, J. Quinn, P. T. Reynolds, H. J. Rose, G. H. Sembroski, A. W. Smith, D. Steele, S. P. Swordy, J. A. Toner, V. V. Vassiliev, S. P. Wakely, T. C. Weekes, R. J. White, D. A. Williams, M. D. Wood, B. Zitzer, H. D. Aller, M. F. Aller, M. Baker, D. Barnaby, M. T. Carini, P. Charlot, J. P. Dumm, N. E. Fields, T. Hovatta, B. Jordan, Y. A. Kovalev, Y. Y. Kovalev, H. A. Krimm, O. M. Kurtanidze, A. Lähteenmäki, J. F. Le Campion, J. Maune, T. Montaruli, A. C. Sadun, S. Smith, M. Tornikoski, M. Turunen, and R. Walters
Subjects: spectral slope variability, bl-lacertae objects, FOS: Physical sciences, bl lacertae objects: individual (markarian 421), proton blazar, tev blazar markarian-421, Astrophysics, timing explorer, Radio spectrum, law.invention, Telescope, Observatory, law, Blazar, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Northern Hemisphere, Astronomy and Astrophysics, gamma-ray emission, lac objects, Wavelength, x-ray, Space and Planetary Science, correlated variability, active galactic nuclei, Spectral energy distribution, Astrophysics - High Energy Astrophysical Phenomena, gamma rays: observations, x-rays: individual (markarian 421)
Abstract: Since September 2005, the Whipple 10m Gamma-ray Telescope has been operated primarily as a blazar monitor. The five Northern Hemisphere blazars that have already been detected at the Whipple Observatory, Markarian 421, H1426+428, Markarian 501, 1ES 1959+650 and 1ES 2344+514, are monitored routinely each night that they are visible. We report on the Markarian 421 observations taken from November 2005 to June 2006 in the gamma-ray, X-ray, optical and radio bands. During this time, Markarian 421 was found to be variable at all wavelengths probed. Both the variability and the correlations among different energy regimes are studied in detail here. A tentative correlation, with large spread, was measured between the X-ray and gamma-ray bands, while no clear correlation was evident among the other energy bands. In addition to this, the well-sampled spectral energy distribution of Markarian 421 (1101+384) is presented for three different activity levels. The observations of the other blazar targets will be reported separately., Comment: 58 pages, 22 Figures. Accepted for publication in ApJ
Published: 2009

93. THE JUNE 2008 FLARE OF MARKARIAN 421 FROM OPTICAL TO TeV ENERGIES

Author: I. Donnarumma, V. Vittorini, S. Vercellone, E. Del Monte, M. Feroci, F. D'Ammando, L. Pacciani, A. W. Chen, M. Tavani, A. Bulgarelli, A. Giuliani, F. Longo, G. Pucella, A. Argan, G. Barbiellini, F. Boffelli, P. Caraveo, P. W. Cattaneo, V. Cocco, E. Costa, G. De Paris, G. Di Cocco, Y. Evangelista, M. Fiorini, T. Froysland, M. Frutti, F. Fuschino, M. Galli, F. Gianotti, C. Labanti, I. Lapshov, F. Lazzarotto, P. Lipari, M. Marisaldi, M. Mastropietro, S. Mereghetti, E. Morelli, A. Morselli, A. Pellizzoni, F. Perotti, P. Picozza, G. Porrovecchio, M. Prest, M. Rapisarda, A. Rappoldi, A. Rubini, P. Soffitta, M. Trifoglio, A. Trois, E. Vallazza, A. Zambra, D. Zanello, C. Pittori, P. Santolamazza, F. Verrecchia, P. Giommi, S. Colafrancesco, L. Salotti, M. Villata, C. M. Raiteri, W. P. Chen, N. V. Efimova, B. Jordan, T. S. Konstantinova, E. Koptelova, O. M. Kurtanidze, V. M. Larionov, J. A. Ros, A. C. Sadun, H. Anderhub, L. A. Antonelli, P. Antoranz, M. Backes, C. Baixeras, S. Balestra, J. A. Barrio, H. Bartko, D. Bastieri, J. Becerra González, J. K. Becker, W. Bednarek, K. Berger, E. Bernardini, A. Biland, R. K. Bock, G. Bonnoli, P. Bordas, D. Borla Tridon, V. Bosch-Ramon, T. Bretz, I. Britvitch, M. Camara, E. Carmona, A. Chilingarian, S. Commichau, J. L. Contreras, J. Cortina, M. T. Costado, S. Covino, V. Curtef, F. Dazzi, A. De Angelis, E. De Cea del Pozo, R. de los Reyes, B. De Lotto, M. De Maria, F. De Sabata, C. Delgado Mendez, A. Dominguez, D. Dorner, M. Doro, D. Elsaesser, M. Errando, D. Ferenc, E. Fernández, R. Firpo, M. V. Fonseca, L. Font, N. Galante, R. J. García López, M. Garczarczyk, M. Gaug, F. Goebel, D. Hadasch, M. Hayashida, A. Herrero, D. Höhne-Mönch, J. Hose, C. C. Hsu, S. Huber, T. Jogler, D. Kranich, A. La Barbera, A. Laille, E. Leonardo, E. Lindfors, S. Lombardi, M. López, E. Lorenz, P. Majumdar, G. Maneva, N. Mankuzhiyil, K. Mannheim, L. Maraschi, M. Mariotti, M. Martínez, D. Mazin, M. Meucci, M. Meyer, J. M. Miranda, R. Mirzoyan, J. Moldón, M. Moles, A. Moralejo, D. Nieto, K. Nilsson, J. Ninkovic, I. Oya, R. Paoletti, J. M. Paredes, M. Pasanen, D. Pascoli, F. Pauss, R. G. Pegna, M. A. Perez-Torres, M. Persic, L. Peruzzo, F. Prada, E. Prandini, N. Puchades, A. Raymers, W. Rhode, M. Ribó, J. Rico, M. Rissi, A. Robert, S. Rügamer, A. Saggion, T. Y. Saito, M. Salvati, M. Sanchez-Conde, P. Sartori, K. Satalecka, V. Scalzotto, V. Scapin, T. Schweizer, M. Shayduk, K. Shinozaki, S. N. Shore, N. Sidro, A. Sierpowska-Bartosik, A. Sillanpää, J. Sitarek, D. Sobczynska, F. Spanier, A. Stamerra, L. S. Stark, L. Takalo, F. Tavecchio, P. Temnikov, D. Tescaro, M. Teshima, M. Tluczykont, D. F. Torres, N. Turini, H. Vankov, A. Venturini, V. Vitale, R. M. Wagner, W. Wittek, V. Zabalza, F. Zandanel, R. Zanin, J. Zapatero, V. Acciari, E. Aliu, T. Arlen, M. Beilicke, W. Benbow, S. M. Bradbury, J. H. Buckley, V. Bugaev, Y. Butt, K. Byrum, A. Cannon, A. Cesarini, Y. C. Chow, L. Ciupik, P. Cogan, P. Colin, W. Cui, M. K. Daniel, R. Dickherber, C. Duke, T. Ergin, S. J. Fegan, J. P. Finley, G. Finnegan, P. Fortin, A. Furniss, D. Gall, G. H. Gillanders, R. Guenette, G. Gyuk, J. Grube, D. Hanna, J. Holder, D. Horan, C. M. Hui, T. Brian Humensky, A. Imran, P. Kaaret, N. Karlsson, M. Kertzman, D. Kieda, J. Kildea, A. Konopelko, H. Krawczynski, F. Krennrich, M. J. Lang, S. LeBohec, G. Maier, A. McCann, M. McCutcheon, A. Milovanovic, P. Moriarty, T. Nagai, R. A. Ong, A. N. Otte, D. Pandel, J. S. Perkins, A. Pichel, M. Pohl, K. Ragan, L. C. Reyes, P. T. Reynolds, E. Roache, H. J. Rose, M. Schroedter, G. H. Sembroski, A. W. Smith, D. Steele, S. P. Swordy, M. Theiling, J. A. Toner, L. Valcarcel, A. Varlotta, S. P. Wakely, J. E. Ward, T. C. Weekes, A. Weinstein, D. A. Williams, S. Wissel, M. Wood, B. Zitzer, I., Donnarumma, V., Vittorini, S., Vercellone, E. D., Monte, M., Feroci, F., D'Ammando, L., Pacciani, A. W., Chen, M., Tavani, A., Bulgarelli, A., Giuliani, Longo, Francesco, G., Pucella, A., Argan, G., Barbiellini, F., Boffelli, P., Caraveo, P. W., Cattaneo, V., Cocco, E., Costa, G. D., Pari, G. D., Cocco, Y., Evangelista, M., Fiorini, T., Froysland, M., Frutti, F., Fuschino, M., Galli, F., Gianotti, C., Labanti, I., Lapshov, F., Lazzarotto, P., Lipari, M., Marisaldi, M., Mastropietro, S., Mereghetti, E., Morelli, A., Morselli, A., Pellizzoni, F., Perotti, P., Picozza, G., Porrovecchio, M., Prest, M., Rapisarda, A., Rappoldi, A., Rubini, P., Soffitta, M., Trifoglio, A., Troi, E., Vallazza, A., Zambra, D., Zanello, C., Pittori, P., Santolamazza, F., Verrecchia, P., Giommi, S., Colafrancesco, L., Salotti, M., Villata, C. M., Raiteri, W. P., Chen, N. V., Efimova, B., Jordan, T. S., Konstantinova, E., Koptelova, O. M., Kurtanidze, V. M., Larionov, J. A., Ro, A. C., Sadun, H., Anderhub, L. A., Antonelli, P., Antoranz, M., Backe, C., Baixera, S., Balestra, J. A., Barrio, H., Bartko, D., Bastieri, J. B., Gonzalez, J. K., Becker, W., Bednarek, K., Berger, E., Bernardini, A., Biland, R. K., Bock, G., Bonnoli, P., Borda, D. B., Tridon, V., Bosch Ramon, T., Bretz, I., Britvitch, M., Camara, E., Carmona, A., Chilingarian, S., Commichau, J. L., Contrera, J., Cortina, M. T., Costado, S., Covino, V., Curtef, F., Dazzi, A. D., Angeli, E. D., Del Pozo, R. D., Reye, B. D., Lotto, M. D., Maria, F. D., Sabata, C. D., Mendez, A., Dominguez, D., Dorner, M., Doro, D., Elsaesser, M., Errando, D., Ferenc, E., Fernandez, R., Firpo, M. V., Fonseca, L., Font, N., Galante, R. J. G., Lopez, M., Garczarczyk, M., Gaug, F., Goebel, D., Hadasch, M., Hayashida, A., Herrero, D., Hohne Monch, J., Hose, C. C., Hsu, S., Huber, T., Jogler, D., Kranich, A. L., Barbera, A., Laille, E., Leonardo, E., Lindfor, S., Lombardi, M., Lopez, E., Lorenz, P., Majumdar, G., Maneva, N., Mankuzhiyil, K., Mannheim, L., Maraschi, M., Mariotti, M., Martinez, D., Mazin, M., Meucci, M., Meyer, J. M., Miranda, R., Mirzoyan, J., Moldon, M., Mole, A., Moralejo, D., Nieto, K., Nilsson, J., Ninkovic, I., Oya, R., Paoletti, J. M., Parede, M., Pasanen, D., Pascoli, F., Pau, R. G., Pegna, M. A., Perez Torre, M., Persic, L., Peruzzo, F., Prada, E., Prandini, N., Puchade, A., Raymer, W., Rhode, M., Ribo, J., Rico, M., Rissi, A., Robert, S., Rugamer, A., Saggion, T. Y., Saito, M., Salvati, M., Sanchez Conde, P., Sartori, K., Satalecka, V., Scalzotto, V., Scapin, T., Schweizer, M., Shayduk, K., Shinozaki, S. N., Shore, N., Sidro, A., Sierpowska Bartosik, A., Sillanpaa, J., Sitarek, D., Sobczynska, F., Spanier, A., Stamerra, L. S., Stark, L., Takalo, F., Tavecchio, P., Temnikov, D., Tescaro, M., Teshima, M., Tluczykont, D. F., Torre, N., Turini, H., Vankov, A., Venturini, V., Vitale, R. M., Wagner, W., Wittek, V., Zabalza, F., Zandanel, R., Zanin, J., Zapatero, V., Acciari, E., Aliu, T., Arlen, M., Beilicke, W., Benbow, S. M., Bradbury, J. H., Buckley, V., Bugaev, Y., Butt, K., Byrum, A., Cannon, A., Cesarini, Y. C., Chow, L., Ciupik, P., Cogan, P., Colin, W., Cui, M. K., Daniel, R., Dickherber, C., Duke, T., Ergin, S. J., Fegan, J. P., Finley, G., Finnegan, P., Fortin, A., Furni, D., Gall, G. H., Gillander, R., Guenette, G., Gyuk, J., Grube, D., Hanna, J., Holder, D., Horan, C. M., Hui, T. B., Humensky, A., Imran, P., Kaaret, N., Karlsson, M., Kertzman, D., Kieda, J., Kildea, A., Konopelko, H., Krawczynski, F., Krennrich, M. J., Lang, S., Lebohec, G., Maier, A., Mccann, M., Mccutcheon, A., Milovanovic, P., Moriarty, T., Nagai, R. A., Ong, A. N., Otte, D., Pandel, J. S., Perkin, A., Pichel, M., Pohl, K., Ragan, L. C., Reye, P. T., Reynold, E., Roache, H. J., Rose, M., Schroedter, G. H., Sembroski, A. W., Smith, D., Steele, S. P., Swordy, M., Theiling, J. A., Toner, L., Valcarcel, A., Varlotta, S. P., Wakely, J. E., Ward, T. C., Weeke, A., Weinstein, D. A., William, S., Wissel, M., Wood, B., Zitzer, Donnarumma I, Vittorini V, Vercellone S, del Monte E, Feroci M, DAmmando F, Pacciani L, Chen A W, Tavani M, Bulgarelli A, Giuliani A, Longo F, Pucella G, Argan A, Barbiellini G, Boffelli F, Caraveo P, Cattaneo P W, Cocco V, Costa E, DeParis G, Di Cocco G, Evangelista Y, Fiorini M, Froysland T, Frutti M, Fuschino F, Galli M, Gianotti F, Labanti C, Lapshov I, Lazzarotto F, Lipari P, Marisaldi M, Mastropietro M, Mereghetti S, Morelli E, Morselli A, Pellizzoni A, Perotti F, Picozza P, Porrovecchio G, Prest M, Rapisarda M, Rappoldi A, Rubini A, Soffitta P, Trifoglio M, Trois A, Vallazza E, Zambra A, Zanello D, Pittori C, Santolamazza P, Verrecchia F, Giommi P, Colafrancesco S, Salotti L, Villata M, Raiteri C M, Chen W P, Efimova N V, Jordan B, Konstantinova T S, Koptelova E, Kurtanidze O M, Larionov V M, Ros J A, Sadun A C, Anderhub H, Antonelli L A, Antoranz P, Backes M, Baixeras C, Balestra S, Barrio J A, Bartko H, Bastieri D, González J Becerra, Becker J K, Bednarek W, Berger K, Bernardini E, Biland A, Bock R K, Bonnoli G, Bordas P, Tridon D Borla, Bosch-Ramon V, Bretz T, Britvitch I, Camara M, Carmona E, Chilingarian A, Commichau S, Contreras J L, Cortina J, Costado M T, Covino S, Curtef V, Dazzi F, DeAngelis A, DeCea del Pozo E, de los Reyes R, DeLotto B, DeMaria M, DeSabata F, Mendez C Delgado, Dominguez A, Dorner D, Doro M, Elsaesser D, Errando M, Ferenc D, Fernández E, Firpo R, Fonseca M V, Font L, Galante N, García López R J, Garczarczyk M, Gaug M, Goebel F, Hadasch D, Hayashida M, Herrero A, Höhne-Mönch D, Hose J, Hsu C C, Huber S, Jogler T, Kranich D, La Barbera A, Laille A, Leonardo E, Lindfors E, Lombardi S, López M, Lorenz E, Majumdar P, Maneva G, Mankuzhiyil N, Mannheim K, Maraschi L, Mariotti M, Martínez M, Mazin D, Meucci M, Meyer M, Miranda J M, Mirzoyan R, Moldón J, Moles M, Moralejo A, Nieto D, Nilsson K, Ninkovic J, Oya I, Paoletti R, Paredes J M, Pasanen M, Pascoli D, Pauss F, Pegna R G, Perez-Torres M A, Persic M, Peruzzo L, Prada F, Prandini E, Puchades N, Raymers A, Rhode W, Ribó M, Rico J, Rissi M, Robert A, Rügamer S, Saggion A, Saito T Y, Salvati M, Sanchez-Conde M, Sartori P, Satalecka K, Scalzotto V, Scapin V, Schweizer T, Shayduk M, Shinozaki K, Shore S N, Sidro N, Sierpowska-Bartosik A, Sillanpää A, Sitarek J, Sobczynska D, Spanier F, Stamerra A, Stark L S, Takalo L, Tavecchio F, Temnikov P, Tescaro D, Teshima M, Tluczykont M, Torres D F, Turini N, Vankov H, Venturini A, Vitale V, Wagner R M, Wittek W, Zabalza V, Zandanel F, Zanin R, Zapatero J, Acciari V, Aliu E, Arlen T, Beilicke M, Benbow W, Bradbury S M, Buckley J H, Bugaev V, Butt Y, Byrum K, Cannon A, Cesarini A, Chow Y C, Ciupik L, Cogan P, Colin P, Cui W, Daniel M K, Dickherber R, Duke C, Ergin T, Fegan S J, Finley J P, Finnegan G, Fortin P, Furniss A, Gall D, Gillanders G H, Guenette R, Gyuk G, Grube J, Hanna D, Holder J, Horan D, Hui C M, Humensky T Brian, Imran A, Kaaret P, Karlsson N, Kertzman M, Kieda D, Kildea J, Konopelko A, Krawczynski H, Krennrich F, Lang M J, LeBohec S, Maier G, McCann A, McCutcheon M, Milovanovic A, Moriarty P, Nagai T, Ong R A, Otte A N, Pandel D, Perkins J S, Pichel A, Pohl M, Ragan K, Reyes L C, Reynolds P T, Roache E, Rose H J, Schroedter M, Sembroski G H, Smith A W, Steele D, Swordy S P, Theiling M, Toner J A, Valcarcel L, Varlotta A, Wakely S P, Ward J E, Weekes T C, Weinstein A, Williams D A, Wissel S, Wood M, and Zitzer B
Subjects: campaign, Raigs còsmics, BL Lacertae: individual: Mrk421, galaxies: jets, X-Rays: Galaxies, gamma rays: observations, radiation mechanisms: nonthermal, bl-lacertae objects, blazars, Flux, Astrophysics, 01 natural sciences, 7. Clean energy, High Energy Gamma-ray Astronomy, law.invention, Raigs gamma, law, optical, MAGIC (telescope), Agile, blazr, X-ray, gamma, high energy observation, 010303 astronomy & astrophysics, webt, Physics, x-ray-spectra, Astrophysics (astro-ph), gamma-rays, lac objects, xmm-newton, Spectral energy distribution, Electrónica, Física nuclear, Raigs X, Electricidad, Flare, outburst, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, 0103 physical sciences, X-rays, BL Lacertae objects: individual (Mrk 421) – gamma rays: observations – galaxies: jets – radiation mechanisms: non-thermal – X-rays: galaxies, Blazar, Cosmic rays, 010308 nuclear & particles physics, Gamma rays, Astronomy and Astrophysics, Active Galactic Nuclei, radiation mechanisms: non-thermal, Light curve, Galaxies, Galàxies, MAGIC telescope, Space and Planetary Science, Very High Energy Gamma-ray Astronomy, ddc:520, AGILE satellite, bl lacertae objects: individual (mrk 421), Energy (signal processing), Lepton
Abstract: We present optical, X-ray, high energy ($\lessapprox 30$ GeV) and very high energy ($\gtrapprox 100$ GeV; VHE) observations of the high-frequency peaked blazar Mrk 421 taken between 2008 May 24 and June 23. A high energy $\gamma$-ray signal was detected by AGILE with \sqrt{TS}=4.5 on June 9--15, with $F(E>100 \mathrm{MeV})= 42^{+14}_{-12}\times 10^{-8}$ photons cm$^{-2}$ s$^{-1}$. This flaring state is brighter than the average flux observed by EGRET by a factor of $\sim$3, but still consistent with the highest EGRET flux. In hard X-rays (20-60 keV) SuperAGILE resolved a 5-day flare (June 9-15) peaking at $\sim$ 55 mCrab. SuperAGILE, RXTE/ASM and Swift/BAT data show a correlated flaring structure between soft and hard X-rays. Hints of the same flaring behavior are also detected in the simultaneous optical data provided by the GASP-WEBT. A Swift/XRT observation near the flaring maximum revealed the highest 2-10 keV flux ever observed from this source, of 2.6 $\times 10^{-9}$ erg cm$^{-2}$ s$^{-1}$ (i.e. > 100 mCrab). A peak synchrotron energy of $\sim$3 keV was derived, higher than typical values of $\sim$0.5-1 keV. VHE observations with MAGIC and VERITAS on June 6-8 show the flux peaking in a bright state, well correlated with the X-rays. This extraordinary set of simultaneous data, covering a twelve-decade spectral range, allowed for a deep analysis of the spectral energy distribution as well as of correlated light curves. The $\gamma$-ray flare can be interpreted within the framework of the synchrotron self-Compton model in terms of a rapid acceleration of leptons in the jet., Comment: accepted for publication in ApJL, 7 pages, 2 figures, 1 table
Published: 2009
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94. VERITAS Observations of the Coma Cluster of Galaxies

Author: J. S. Perkins
Subjects: Physics, biology, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), Northern Hemisphere, Gamma ray, Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, biology.organism_classification, 01 natural sciences, Galaxy, 0103 physical sciences, Coma Cluster, Cluster (physics), Egret, 010303 astronomy & astrophysics, Galaxy cluster, Cherenkov radiation, Astrophysics::Galaxy Astrophysics
Abstract: Clusters of galaxies are one of the few prominent classes of objects predicted to emit gamma rays not yet detected by satellites like EGRET or ground-based Imaging Atmospheric Cherenkov Telescopes (IACTs). The detection of Very High Energy (VHE, E > 100 GeV) gamma rays from galaxy clusters would provide insight into the morphology of non-thermal particles and fields in clusters. VERITAS, an array of four 12-meter diameter IACTs, is ideally situated to observe the massive Coma cluster, one of the best cluster candidates in the Northern Hemisphere. This contribution details the results of VERITAS observations of the Coma cluster of galaxies during the 2007-2008 observing season., Submitted to Proceedings of "4th Heidelberg International Symposium on High Energy Gamma-Ray Astronomy 2008"
Published: 2008

95. Observation of gamma‐ray emission from the galaxy m87 above 250 gev with veritas1

Author: V. A. Acciari, M. Beilicke, G. Blaylock, S. M. Bradbury, J. H. Buckley, V. Bugaev, Y. Butt, O. Celik, A. Cesarini, L. Ciupik, P. Cogan, P. Colin, W. Cui, M. K. Daniel, C. Duke, T. Ergin, A. D. Falcone, S. J. Fegan, J. P. Finley, G. Finnegan, P. Fortin, L. F. Fortson, K. Gibbs, G. H. Gillanders, J. Grube, R. Guenette, G. Gyuk, D. Hanna, E. Hays, J. Holder, D. Horan, S. B. Hughes, M. C. Hui, T. B. Humensky, A. Imran, P. Kaaret, M. Kertzman, D. B. Kieda, J. Kildea, A. Konopelko, H. Krawczynski, F. Krennrich, M. J. Lang, S. LeBohec, K. Lee, G. Maier, A. McCann, M. McCutcheon, J. Millis, P. Moriarty, R. Mukherjee, T. Nagai, R. A. Ong, D. Pandel, J. S. Perkins, M. Pohl, J. Quinn, K. Ragan, P. T. Reynolds, H. J. Rose, M. Schroedter, G. H. Sembroski, A. W. Smith, D. Steele, S. P. Swordy, A. Syson, J. A. Toner, L. Valcarcel, V. V. Vassiliev, S. P. Wakely, J. E. Ward, T. C. Weekes, A. Weinstein, R. J. White, D. A. Williams, S. A. Wissel, M. D. Wood, and B. Zitzer
Subjects: unified schemes, Active galactic nucleus, Radio galaxy, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, galaxies : individual (m87, ngc 4486, virgo a), 01 natural sciences, Observatory, jet, 0103 physical sciences, gamma rays : observations, crab-nebula, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, tev emission, 010308 nuclear & particles physics, variability, Gamma ray, telescope observations, Astronomy and Astrophysics, Radius, Cherenkov Telescope Array, lac objects, Galaxy, x-ray, 13. Climate action, Space and Planetary Science, markarian-421, High Energy Physics::Experiment, Radio wave, supermassive black-hole
Abstract: The multiwavelength observation of the nearby radio galaxy M87 provides a unique opportunity to study in detail processes occurring in Active Galactic Nuclei from radio waves to TeV gamma-rays. Here we report the detection of gamma-ray emission above 250 GeV from M87 in spring 2007 with the VERITAS atmospheric Cherenkov telescope array and discuss its correlation with the X-ray emission. The gamma-ray emission is measured to be point-like with an intrinsic source radius less than 4.5 arcmin. The differential energy spectrum is fitted well by a power-law function: dPhi/dE=(7.4+-1.3_{stat}+-1.5_{sys})(E/TeV)^{-2.31+-0.17_{stat}+-0.2_{sys}} 10^{-9}m^{-2}s^{-1}TeV^{-1}. We show strong evidence for a year-scale correlation between the gamma-ray flux reported by TeV experiments and the X-ray emission measured by the ASM/RXTE observatory, and discuss the possible short-time-scale variability. These results imply that the gamma-ray emission from M87 is more likely associated with the core of the galaxy than with other bright X-ray features in the jet.
Published: 2008

96. VERITAS Observations of the gamma-Ray Binary LS I +61 303

Author: V. A. Acciari, M. Beilicke, G. Blaylock, S. M. Bradbury, J. H. Buckley, V. Bugaev, Y. Butt, K. L. Byrum, O. Celik, A. Cesarini, L. Ciupik, Y. C. K. Chow, P. Cogan, P. Colin, W. Cui, M. K. Daniel, C. Duke, T. Ergin, A. D. Falcone, S. J. Fegan, J. P. Finley, P. Fortin, L. F. Fortson, D. Gall, K. Gibbs, G. H. Gillanders, J. Grube, R. Guenette, D. Hanna, E. Hays, J. Holder, D. Horan, S. B. Hughes, C. M. Hui, T. B. Humensky, P. Kaaret, D. B. Kieda, J. Kildea, A. Konopelko, H. Krawczynski, F. Krennrich, M. J. Lang, S. LeBohec, K. Lee, G. Maier, A. McCann, M. McCutcheon, J. Millis, P. Moriarty, R. Mukherjee, T. Nagai, R. A. Ong, D. Pandel, J. S. Perkins, F. Pizlo, M. Pohl, J. Quinn, K. Ragan, P. T. Reynolds, H. J. Rose, M. Schroedter, G. H. Sembroski, A. W. Smith, D. Steele, S. P. Swordy, J. A. Toner, L. Valcarcel, V. V. Vassiliev, R. Wagner, S. P. Wakely, J. E. Ward, T. C. Weekes, A. Weinstein, R. J. White, D. A. Williams, S. A. Wissel, M. Wood, and B. Zitzer
Subjects: catalog, Photon, Astrophysics::High Energy Astrophysical Phenomena, Flux, Binary number, FOS: Physical sciences, Astrophysics, 01 natural sciences, Power law, Standard deviation, spectrum, microquasar ls-i+61-303, ls-i +61-degrees-303, emission, 0103 physical sciences, Energy spectrum, gamma rays : observations, 010303 astronomy & astrophysics, acceleration of particles, Physics, lsi+61-degrees-303, model, 010308 nuclear & particles physics, stars : individual (ls i+61 303), Astrophysics (astro-ph), Gamma ray, Astronomy and Astrophysics, astronomy, modulation, Crab Nebula, Space and Planetary Science, High Energy Physics::Experiment, binaries : general, discovery
Abstract: LS I +61 303 is one of only a few high-mass X-ray binaries currently detected at high significance in very high energy gamma-rays. The system was observed over several orbital cycles (between September 2006 and February 2007) with the VERITAS array of imaging air-Cherenkov telescopes. A signal of gamma-rays with energies above 300 GeV is found with a statistical significance of 8.4 standard deviations. The detected flux is measured to be strongly variable; the maximum flux is found during most orbital cycles at apastron. The energy spectrum for the period of maximum emission can be characterized by a power law with a photon index of Gamma=2.40+-0.16_stat+-0.2_sys and a flux above 300 GeV corresponding to 15-20% of the flux from the Crab Nebula., Comment: accepted for publication in The Astrophysical Journal
Published: 2008
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97. Status of the VERITAS Observatory

Author: J. Holder, V. A. Acciari, E. Aliu, T. Arlen, M. Beilicke, W. Benbow, S. M. Bradbury, J. H. Buckley, V. Bugaev, Y. Butt, K. L. Byrum, A. Cannon, O. Celik, A. Cesarini, L. Ciupik, Y. C. K. Chow, P. Cogan, P. Colin, W. Cui, M. K. Daniel, T. Ergin, A. D. Falcone, S. J. Fegan, J. P. Finley, G. Finnegan, P. Fortin, L. F. Fortson, A. Furniss, G. H. Gillanders, J. Grube, R. Guenette, G. Gyuk, D. Hanna, E. Hays, D. Horan, C. M. Hui, T. B. Humensky, A. Imran, P. Kaaret, N. Karlsson, M. Kertzman, D. B. Kieda, J. Kildea, A. Konopelko, H. Krawczynski, F. Krennrich, M. J. Lang, S. LeBohec, G. Maier, A. McCann, M. McCutcheon, P. Moriarty, R. Mukherjee, T. Nagai, J. Niemiec, R. A. Ong, D. Pandel, J. S. Perkins, M. Pohl, J. Quinn, K. Ragan, L. C. Reyes, P. T. Reynolds, H. J. Rose, M. Schroedter, G. H. Sembroski, A. W. Smith, D. Steele, S. P. Swordy, J. A. Toner, L. Valcarcel, V. V. Vassiliev, R. Wagner, S. P. Wakely, J. E. Ward, T. C. Weekes, A. Weinstein, R. J. White, D. A. Williams, S. A. Wissel, M. Wood, B. Zitzer, Felix A. Aharonian, Werner Hofmann, and Frank Rieger
Subjects: Physics, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, Astrophysics (astro-ph), Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, IACT, Astrophysics, 01 natural sciences, law.invention, Telescope, Technical performance, Observatory, law, 0103 physical sciences, High Energy Physics::Experiment, 010303 astronomy & astrophysics, Cherenkov radiation, Astrophysics::Galaxy Astrophysics
Abstract: VERITAS, an Imaging Atmospheric Cherenkov Telescope (IACT) system for gammma-ray astronomy in the GeV-TeV range, has recently completed its first season of observations with a full array of four telescopes. A number of astrophysical gamma-ray sources have been detected, both galactic and extragalactic, including sources previously unknown at TeV energies. We describe the status of the array and some highlight results, and assess the technical performance, sensitivity and shower reconstruction capabilities., Comment: Submitted to Proceedings of "4th Heidelberg International Symposium on High Energy Gamma-Ray Astronomy 2008"
Published: 2008
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98. Control, Monitoring and Analysis Software for the VERITAS Array

Author: J. S. Perkins
Subjects: Engineering, Data acquisition, business.industry, Control (management), Real-time computing, Offline analysis, Analysis software, Astronomical telescopes, Software system, business, Cherenkov radiation, Online analysis
Abstract: VERITAS is an array of four 12 m diameter Atmospheric Cherenkov Telescopes located in southern Arizona operating since January 2007. In this contribution we discuss the various software systems needed to operate the array including the data acquisition, online analysis, real time hardware monitoring and offline analysis.
Published: 2007
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99. Whipple telescope observations of LS I +61 303: 2004–2006

Author: A. Smith, R. W. Atkins, S. Bradbury, O. Celik, Y. C. K. Chow, P. Cogan, C. Dowdall, S. J. Fegan, P. Fortin, D. Gall, G. H. Gillanders, J. Grube, K. J. Gutierrez, T. A. Hall, D. Hanna, J. Holder, D. Horan, S. B. Hughes, T. B. Humensky, I. Jung, P. Kaaret, G. Kenny, M. Kertzman, D. B. Kieda, A. Konopelko, H. Krawczynski, F. Krennrich, M. J. Lang, S. Le Bohec, G. Maier, J. Millis, P. Moriarty, R. A. Ong, J. S. Perkins, K. Ragan, G. H. Sembroski, J. A. Toner, L. Valcarcel, V. V. Vassiliev, R. G. Wagner, S. P. Wakely, T. C. Weekes, R. J. White, and D. A. Williams
Published: 2007
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100. The first veritas telescope

Author: Geza Gyuk, A. Milovanovic, Philip Kaaret, F. Krennrich, A. Syson, M. K. Daniel, Gernot Maier, D. A. Carter-Lewis, G. E. Kenny, J. P. Finley, K. Ragan, D. Horan, T. C. Weekes, S. P. Wakely, Y. C. K. Chow, Abraham D. Falcone, C. Duke, R. A. Ong, John Toner, F. Pizlo, R. G. Wagner, H. Manseri, E. Roache, J. Grube, S. LeBohec, S. P. Swordy, P. A. Ogden, Reshmi Mukherjee, Jamie Holder, M. J. Lang, I. Jung, K. J. Gutierrez, R. J. White, John L. Quinn, S. B. Hughes, Henric Krawczynski, P. Moriarty, K. G. Gibbs, S. M. Bradbury, Karen Byrum, G. Sleege, John Kildea, E.K. Little, M. Schroedter, G. Blaylock, J. Hall, J. S. Perkins, David A. Williams, C. Dowdall, P. Fortin, H. J. Rose, P. Cogan, Martin Pohl, R. W. Atkins, J. H. Buckley, P. T. Reynolds, D. Petry, E. Hays, V. V. Vassiliev, David Kieda, Lucy Fortson, Paul Dowkontt, Wei Cui, L. Valcarcel, H. M. Badran, O. J. Glidewell, D. S. Hanna, A. Imran, E. Linton, J. Knapp, I. de la Calle Perez, Thomas Brian Humensky, G. H. Sembroski, G. H. Gillanders, O. Celik, S. J. Fegan, and D. Steele
Subjects: tev gamma-rays, Astrophysics::High Energy Astrophysical Phenomena, Monte Carlo method, FOS: Physical sciences, X-ray telescope, Astrophysics, system, 01 natural sciences, law.invention, spectrum, Telescope, project, law, 0103 physical sciences, Calibration, Astrophysics::Solar and Stellar Astrophysics, crab-nebula, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Cherenkov radiation, gamma ray astronomy, cherenkov telescopes, atmospheric cherenkov telescope, imaging technique, Physics, 010308 nuclear & particles physics, Astrophysics (astro-ph), Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, Gamma-ray astronomy, Cherenkov Telescope Array, Crab Nebula, Astrophysics::Earth and Planetary Astrophysics
Abstract: The first atmospheric Cherenkov telescope of VERITAS (the Very Energetic Radiation Imaging Telescope Array System) has been in operation since February 2005. We present here a technical description of the instrument and a summary of its performance. The calibration methods are described, along with the results of Monte Carlo simulations of the telescope and comparisons between real and simulated data. The analysis of TeV $\gamma$-ray observations of the Crab Nebula, including the reconstructed energy spectrum, is shown to give results consistent with earlier measurements. The telescope is operating as expected and has met or exceeded all design specifications., Comment: Accepted by Astroparticle Physics
Published: 2006

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