Author: "Johnson, W. N." - Searchworks@Jio Institute Digital Library Search Results

Your search keyword '"Johnson, W. N."' showing total 902 results

Start Over Author "Johnson, W. N."

902 results on '"Johnson, W. N."'

1. The spectrum of isotropic diffuse gamma-ray emission between 100 MeV and 820 GeV

Author: The Fermi LAT collaboration, Ackermann, M., Ajello, M., Albert, A., Atwood, W. B., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Bissaldi, E., Blandford, R. D., Bloom, E. D., Bottacini, E., Brandt, T. J., Bregeon, J., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caragiulo, M., Caraveo, P. A., Cavazzuti, E., Cecchi, C., Charles, E., Chekhtman, A., Chiang, J., Chiaro, G., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Cuoco, A., Cutini, S., D'Ammando, F., de Angelis, A., de Palma, F., Dermer, C. D., Digel, S. W., Silva, E. do Couto e, Drell, P. S., Favuzzi, C., Ferrara, E. C., Focke, W. B., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Germani, S., Giglietto, N., Giommi, P., Giordano, F., Giroletti, M., Godfrey, G., Gomez-Vargas, G. A., Grenier, I. A., Guiriec, S., Gustafsson, M., Hadasch, D., Hayashi, K., Hays, E., Hewitt, J. W., Ippoliti, P., Jogler, T., Jóhannesson, G., Johnson, A. S., Johnson, W. N., Kamae, T., Kataoka, J., Knödlseder, J., Kuss, M., Larsson, S., Latronico, L., Li, J., Li, L., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Manfreda, A., Massaro, F., Mayer, M., Mazziotta, M. N., McEnery, J. E., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nemmen, R., Nuss, E., Ohsugi, T., Omodei, N., 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., Razzaque, S., Reimer, A., Reimer, O., Reposeur, T., Ritz, S., Romani, R. W., Sánchez-Conde, M., Schaal, M., Schulz, A., Sgrò, C., Siskind, E. J., Spandre, G., Spinelli, P., Strong, A. W., Suson, D. J., Takahashi, H., Thayer, J. G., Thayer, J. B., Tibaldo, L., Tinivella, M., Torres, D. F., Tosti, G., Troja, E., Uchiyama, Y., Vianello, G., Werner, M., Winer, B. L., Wood, K. S., Wood, M., Zaharijas, G., and Zimmer, S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The {\gamma}-ray sky can be decomposed into individually detected sources, diffuse emission attributed to the interactions of Galactic cosmic rays with gas and radiation fields, and a residual all-sky emission component commonly called the isotropic diffuse {\gamma}-ray background (IGRB). The IGRB comprises all extragalactic emissions too faint or too diffuse to be resolved in a given survey, as well as any residual Galactic foregrounds that are approximately isotropic. The first IGRB measurement with the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope (Fermi) used 10 months of sky-survey data and considered an energy range between 200 MeV and 100 GeV. Improvements in event selection and characterization of cosmic-ray backgrounds, better understanding of the diffuse Galactic emission, and a longer data accumulation of 50 months, allow for a refinement and extension of the IGRB measurement with the LAT, now covering the energy range from 100 MeV to 820 GeV. The IGRB spectrum shows a significant high-energy cutoff feature, and can be well described over nearly four decades in energy by a power law with exponential cutoff having a spectral index of $2.32\pm0.02$ and a break energy of $(279\pm52)$ GeV using our baseline diffuse Galactic emission model. The total intensity attributed to the IGRB is $(7.2\pm0.6) \times 10^{-6}$ cm$^{-2}$ s$^{-1}$ sr$^{-1}$ above 100 MeV, with an additional $+15$%/$-30$% systematic uncertainty due to the Galactic diffuse foregrounds., Comment: Accepted by The Astrophysical Journal
Published: 2014
Full Text: View/download PDF

2. The CsI calorimeter for AMEGO-X

Author: Woolf, R. S., primary, Shy, D., additional, Wulf, E. A., additional, Sleator, C. C., additional, Johnson-Rambert, M., additional, Johnson, W. N., additional, Grove, J. E., additional, and Phlips, B. F., additional
Published: 2023
Full Text: View/download PDF

3. Binary Millisecond Pulsar Discovery via Gamma-Ray Pulsations

Author: Pletsch, H. J., Guillemot, L., Fehrmann, H., Allen, B., Kramer, M., Aulbert, C., Ackermann, M., Ajello, M., de Angelis, A., Atwood, W. B., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Borgland, A. W., Bottacini, E., Brandt, T. J., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Celik, Ö., Charles, E., Chaves, R. C. G., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Cutini, S., D'Ammando, F., Dermer, C. D., Digel, S. W., Drell, P. S., Drlica-Wagner, A., Dubois, R., Dumora, D., Favuzzi, C., Ferrara, E. C., Franckowiak, A., Fukazawa, Y., Fusco, P., Gargano, F., Gehrels, N., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Godfrey, G., Grenier, I. A., Grondin, M. -H., Grove, J. E., Guiriec, S., Hadasch, D., Hanabata, Y., Harding, A. K., Hartog, P. R. den, Hayashida, M., Hays, E., Hill, A. B., Hou, X., Hughes, R. E., Johannesson, G., Jackson, M. S., Jogler, T., Johnson, A. S., Johnson, W. N., Kataoka, J., Kerr, M., Knödlseder, J., Kuss, M., Lande, J., Larsson, S., Latronico, L., Lemoine-Goumard, M., Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., Massaro, F., Mayer, M., Mazziotta, M. N., McEnery, J. E., Mehault, J., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nakamori, T., Nemmen, R., Nuss, E., Ohno, M., Ohsugi, T., Omodei, N., Orienti, M., Orlando, E., de Palma, F., Paneque, D., Perkins, J. S., Piron, F., Pivato, G., Porter, T. A., Raino, S., Rando, R., Ray, P. S., Razzano, M., Reimer, A., Reimer, O., Reposeur, T., Ritz, S., Romani, R. W., Romoli, C., Sanchez, D. A., Parkinson, P. M. Saz, Schulz, A., Sgro, C., Silva, E. do Couto e, Siskind, E. J., Smith, D. A., Spandre, G., Spinelli, P., Suson, D. J., Takahashi, H., Tanaka, T., Thayer, J. B., Thayer, J. G., Thompson, D. J., Tibaldo, L., Tinivella, M., Troja, E., Usher, T. L., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Waite, A. P., Winer, B. L., Wood, K. S., Wood, M., Yang, Z., and Zimmer, S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Galaxy Astrophysics, General Relativity and Quantum Cosmology
Abstract: Millisecond pulsars, old neutron stars spun-up by accreting matter from a companion star, can reach high rotation rates of hundreds of revolutions per second. Until now, all such "recycled" rotation-powered pulsars have been detected by their spin-modulated radio emission. In a computing-intensive blind search of gamma-ray data from the Fermi Large Area Telescope (with partial constraints from optical data), we detected a 2.5-millisecond pulsar, PSR J1311-3430. This unambiguously explains a formerly unidentified gamma-ray source that had been a decade-long enigma, confirming previous conjectures. The pulsar is in a circular orbit with an orbital period of only 93 minutes, the shortest of any spin-powered pulsar binary ever found., Comment: 14 pages, 3 figures. Science Express (25 October 2012); in press
Published: 2012
Full Text: View/download PDF

4. Simultaneous multi-wavelength campaign on PKS 2005-489 in a high state

Author: Collaboration, The H. E. S. S., Collaboration, the Fermi LAT, Abramowski, A., Acero, F., Aharonian, F., Akhperjanian, A. G., Anton, G., Barnacka, A., de Almeida, U. Barres, Bazer-Bachi, A. R., Becherini, Y., Becker, J., Behera, B., Bernlöhr, K., Bochow, A., Boisson, C., Bolmont, J., Bordas, P., Borrel, V., Brucker, J., Brun, F., Brun, P., Bulik, T., Büsching, I., Casanova, S., Cerruti, M., Chadwick, P. M., Charbonnier, A., Chaves, R. C. G., Cheesebrough, A., Chounet, L. -M., Clapson, A. C., Coignet, G., Conrad, J., Dalton, M., Daniel, M. K., Davids, I. D., Degrange, B., Deil, C., Dickinson, H. J., Djannati-Ataï, A., Domainko, W., Drury, L. O'C., Dubois, F., Dubus, G., Dyks, J., Dyrda, M., Egberts, K., Eger, P., Espigat, P., Fallon, L., Farnier, C., Fegan, S., Feinstein, F., Fernandes, M. V., Fiasson, A., Fontaine, G., Förster, A., Füßling, M., Gabici, S., Gallant, Y. A., Gast, H., Gérard, L., Gerbig, D., Giebels, B., Glicenstein, J. F., Glück, B., Goret, P., Göring, D., Hague, J. D., Hampf, D., Hauser, M., Heinz, S., Heinzelmann, G., Henri, G., Hermann, G., Hinton, J. A., Hoffmann, A., Hofmann, W., Hofverberg, P., Horns, D., Jacholkowska, A., de Jager, O. C., Jahn, C., Jamrozy, M., Jung, I., Kastendieck, M. A., Katarzyński, K., Katz, U., Kaufmann, S., Keogh, D., Kerschhaggl, M., Khangulyan, D., Khélifi, B., Klochkov, D., Kluźniak, W., Kneiske, T., Komin, Nu., Kosack, K., Kossakowski, R., Laffon, H., Lamanna, G., Lenain, J. -P., Lennarz, D., Lohse, T., Lopatin, A., Lu, C. -C., Marandon, V., Marcowith, A., Masbou, J., Maurin, D., Maxted, N., McComb, T. J. L., Medina, M. C., Méhault, J., Nguyen, N., Moderski, R., Moulin, E., Naumann-Godo, M., de Naurois, M., Nedbal, D., Nekrassov, D., Nicholas, B., Niemiec, J., Nolan, S. J., Ohm, S., Olive, J-F., Wilhelmi, E. de Oña, Opitz, B., Ostrowski, M., Panter, M., Arribas, M. Paz, Pedaletti, G., Pelletier, G., Petrucci, P. -O., Pita, S., Pühlhofer, G., Punch, M., Quirrenbach, A., Raue, M., Rayner, S. M., Reimer, A., Reimer, O., Renaud, M., Reyes, R. de los, Rieger, F., Ripken, J., Rob, L., Rosier-Lees, S., Rowell, G., Rudak, B., Rulten, C. B., Ruppel, J., Ryde, F., Sahakian, V., Santangelo, A., Schlickeiser, R., Schöck, F. M., Schönwald, A., Schwanke, U., Schwarzburg, S., Schwemmer, S., Shalchi, A., Sikora, M., Skilton, J. L., Sol, H., Spengler, G., Stawarz, Ł., Steenkamp, R., Stegmann, C., Stinzing, F., Sushch, I., Szostek, A., Tam, P. H., Tavernet, J. -P., Terrier, R., Tibolla, O., Tluczykont, M., Valerius, K., van Eldik, C., Vasileiadis, G., Venter, C., Vialle, J. P., Viana, A., Vincent, P., Vivier, M., Völk, H. J., Volpe, F., Vorobiov, S., Vorster, M., Wagner, S. J., Ward, M., Wierzcholska, A., Zajczyk, A., Zdziarski, A. A., Zech, A., Zechlin, H. -S., Abdo, A. A., Ackermann, M., Ajello, M., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bonamente, E., Borgland, A. W., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Cannon, A., Caraveo, P. A., Carrigan, S., Casandjian, J. M., Cavazzuti, E., Cecchi, C., Çelik, Ö., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Cutini, S., Dermer, C. D., de Palma, F., Silva, E. do Couto e, Drell, P. S., Dubois, R., Dumora, D., Escande, L., Favuzzi, C., Ferrara, E. C., Focke, W. B., Fortin, P., Frailis, M., Fukazawa, Y., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giglietto, N., Giommi, P., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Grove, J. E., Guiriec, S., Hadasch, D., Hays, E., Horan, D., Hughes, R. E., Jóhannesson, G., Johnson, A. S., Johnson, W. N., Kamae, T., Katagiri, H., Kataoka, J., Knödlseder, J., Kuss, M., Lande, J., Latronico, L., Lee, S. -H., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Makeev, A., Mazziotta, M. N., McConville, W., McEnery, J. E., Michelson, P. F., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nakamori, T., Nishino, S., Nolan, P. L., Norris, J. P., Nuss, E., Ohsugi, T., Okumura, A., Omodei, N., Orlando, E., Ormes, J. F., Ozaki, M., Paneque, D., Panetta, J. H., Parent, D., Pelassa, V., Pepe, M., Pesce-Rollins, M., Piron, F., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Sadrozinski, H. F. -W., Sanchez, D., Sander, A., Sgrò, C., Siskind, E. J., Smith, P. D., Spandre, G., Spinelli, P., Strickman, M. S., Suson, D. J., Takahashi, H., Takahashi, T., Tanaka, T., Thayer, J. B., Thayer, J. G., Thompson, D. J., Tibaldo, L., Torres, D. F., Tosti, G., Tramacere, A., Troja, E., Uehara, T., Usher, T. L., Vandenbroucke, J., Vianello, G., Vilchez, N., Vitale, V., Waite, A. P., Wang, P., Winer, B. L., Wood, K. S., Yang, Z., Ylinen, T., and Ziegler, M.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The high-frequency peaked BL Lac object PKS 2005-489 was the target of a multi-wavelength campaign with simultaneous observations in the TeV gamma-ray (H.E.S.S.), GeV gamma-ray (Fermi/LAT), X-ray (RXTE, Swift), UV (Swift) and optical (ATOM, Swift) bands. This campaign was carried out during a high flux state in the synchrotron regime. The flux in the optical and X-ray bands reached the level of the historical maxima. The hard GeV spectrum observed with Fermi/LAT connects well to the very high energy (VHE, E>100GeV) spectrum measured with H.E.S.S. with a peak energy between ~5 and 500 GeV. Compared to observations with contemporaneous coverage in the VHE and X-ray bands in 2004, the X-ray flux was ~50 times higher during the 2009 campaign while the TeV gamma-ray flux shows marginal variation over the years. The spectral energy distribution during this multi-wavelength campaign was fit by a one zone synchrotron self-Compton model with a well determined cutoff in X-rays. The parameters of a one zone SSC model are inconsistent with variability time scales. The variability behaviour over years with the large changes in synchrotron emission and small changes in the inverse Compton emission does not warrant an interpretation within a one-zone SSC model despite an apparently satisfying fit to the broadband data in 2009., Comment: published in A&A, 9pages, 4figures. Due to some style difficulties using the standard style file with the long author list, the abstract has been included manually. A version with the correct style can be found in the website http://www.lsw.uni-heidelberg.de/users/skaufman/publications/aa16170-10published.pdf
Published: 2011
Full Text: View/download PDF

5. Radio and Gamma-Ray Constraints on the Emission Geometry and Birthplace of PSR J2043+2740

Author: Noutsos, A., Abdo, A. A., Ackermann, M., Ajello, M., Ballet, J., Barbiellini, G., Baring, M. G., Bastieri, D., Bechtol, K., Bellazzini, R., Berenji, B., Bonamente, E., Borgland, A. W., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Buehler, R., Busetto, G., Caliandro, G. A., Cameron, R. A., Camilo, F., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Celik, O., Chaty, S., Chekhtman, A., Chiang, J., Ciprini, S., Claus, R., Cognard, I., Cohen-Tanugi, J., Colafrancesco, S., Cutini, S., Dermer, C. D., de Palma, F., Drell, P. S., Dumora, D., Espinoza, C. M., Favuzzi, C., Ferrara, E. C., Focke, W. B., Frailis, M., Freire, P. C. C., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Godfrey, G., Grandi, P., Grenier, I. A., Grove, J. E., Guillemot, L., Guiriec, S., Harding, A. K., Hughes, R. E., Jackson, M. S., Johannesson, G., Johnson, A. S., Johnson, T. J., Johnson, W. N., Johnston, S., Kamae, T., Katagiri, H., Kataoka, J., Knoedlseder, J., Kramer, M., Kuss, M., Lande, J., Lee, S. -H., Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., Lyne, A. G., Makeev, A., Marelli, M., Mazziotta, M. N., McEnery, J. E., Mehault, J., Michelson, P. F., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Naumann-Godo, M., Nolan, P. L., Nuss, E., Ohsugi, T., Okumura, A., Omodei, N., Orlando, E., Ormes, J. F., Panetta, J. H., Parent, D., Pelassa, V., Pepe, M., Persic, M., Pesce-Rollins, M., Piron, F., Porter, T. A., Rain, S., Ray, P. S., Razzano, M., Reimer, A., Reimer, O., Reposeur, T., Romani, R. W., Sadrozinski, H. F. -W., Sander, A., Parkinson, P. M. Saz, Sgro, C., Siskind, E. J., Smith, D. A., Smith, P. D., Spandre, G., Spinelli, P., Stappers, B. W., Strickman, M. S., Suson, D. J., Takahashi, H., Tanaka, T., Theureau, G., Thompson, D. J., Thorsett, S. E., Tibolla, O., Torres, D. F., Tramacere, A., Usher, T. L., Vandenbroucke, J., Vianello, G., Vilchez, N., Villata, M., Vitale, V., von Kienlin, A., Waite, A. P., Wang, P., Watters, K., Weltevrede, P., Winer, B. L., Wood, K. S., and Ziegler, M.
Subjects: Astrophysics - Astrophysics of Galaxies
Abstract: We report on the first year of Fermi gamma-ray observations of pulsed high-energy emission from the old PSR J2043+2740. The study of the gamma-ray efficiency of such old pulsars gives us an insight into the evolution of pulsars' ability to emit in gammma rays as they age. The gamma-ray lightcurve of this pulsar above 0.1 GeV is clearly defined by two sharp peaks, 0.353+/-0.035 periods apart. We have combined the gamma-ray profile characteristics of PSR J2043+2740 with the geometrical properties of the pulsar's radio emission, derived from radio polarization data, and constrained the pulsar-beam geometry in the framework of a Two Pole Caustic and an Outer Gap model. The ranges of magnetic inclination and viewing angle were determined to be {alpha,zeta}~{52-57,61-68} for the Two Pole Caustic model, and {alpha,zeta}~{62-73,74-81} and {alpha,zeta}~{72-83,60-75} for the Outer Gap model. Based on this geometry, we assess possible birth locations for this pulsar and derive a likely proper motion, sufficiently high to be measurable with VLBI. At a characteristic age of 1.2 Myr, PSR J2043+2740 is the third oldest of all discovered, non-recycled, gamma-ray pulsars: it is twice as old as the next oldest, PSR J0357+32, and younger only than the recently discovered PSR J1836+5925 and PSR J2055+25, both of which are at least 5 and 10 times less energetic, respectively., Comment: 17 pages, 6 figures, Accepted for publication in ApJ
Published: 2010
Full Text: View/download PDF

6. The Discovery of gamma-Ray Emission From The Blazar RGB J0710+591

Author: Acciari, V. A., Aliu, E., Arlen, T., Aune, T., Bautista, M., Beilicke, M., Benbow, W., Böttcher, M., Boltuch, D., Bradbury, S. M., Buckley, J. H., Bugaev, V., Byrum, K., Cannon, A., Cesarini, A., Ciupik, L., Cui, W., Dickherber, R., Duke, C., Falcone, A., Finley, J. P., Finnegan, G., Fortson, L., Furniss, A., Galante, N., Gall, D., Gibbs, K., Gillanders, G. H., Godambe, S., Grube, J., Guenette, R., Gyuk, G., Hanna, D., Holder, J., Hui, C. M., Humensky, T. B., Imran, A., Kaaret, P., Karlsson, N., Kertzman, M., Kieda, D., Konopelko, A., Krawczynski, H., Krennrich, F., Lang, M. J., Lamerato, A., LeBohec, S., Maier, G., McArthur, S., McCann, A., McCutcheon, M., Moriarty, P., Mukherjee, R., Ong, R. A., Otte, A. N., Pandel, D., Perkins, J. S., Petry, D., Pichel, A., Pohl, M., Quinn, J., Ragan, K., Reyes, L. C., Reynolds, P. T., Roache, E., Rose, H. J., Roustazadeh, P., Schroedter, M., Sembroski, G. H., Senturk, G. Demet, Smith, A. W., Steele, D., Swordy, S. P., Tešić, G., Theiling, M., Thibadeau, S., Varlotta, A., Vassiliev, V. V., Vincent, S., Wagner, R. G., Wakely, S. P., Ward, J. E., Weekes, T. C., Weinstein, A., Weisgarber, T., Williams, D. A., Wissel, S., Wood, M., Zitzer, B., Ackermann, M., Ajello, M., Antolini, E., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bouvier, A., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Carrigan, S., Casandjian, J. M., Cavazzuti, E., Cecchi, C., Çelik, Ö., Charles, E., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Dermer, C. D., de Palma, F., Silva, E. do Couto e, Drell, P. S., Dubois, R., Dumora, D., Farnier, C., Favuzzi, C., Fegan, S. J., Fortin, P., Frailis, M., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giebels, B., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Grove, J. E., Guiriec, S., Hays, E., Horan, D., Hughes, R. E., Jóhannesson, G., Johnson, A. S., Johnson, W. N., Kamae, T., Katagiri, H., Kataoka, J., Knödlseder, J., Kuss, M., Lande, J., Latronico, L., Lee, S. -H., Garde, M. Llena, Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Makeev, A., Mazziotta, M. N., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nolan, P. L., Norris, J. P., Nuss, E., Ohno, M., Ohsugi, T., Omodei, N., Orlando, E., Ormes, J. F., Paneque, D., Panetta, J. H., Pelassa, V., Pepe, M., Pesce-Rollins, M., Piron, F., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Reimer, A., Reimer, O., Ripken, J., Rodriguez, A. Y., Roth, M., Sadrozinski, H. F. -W., Sanchez, D., Sander, A., Scargle, J. D., Sgrò, C., Siskind, E. J., Smith, P. D., Spandre, G., Spinelli, P., Strickman, M. S., Suson, D. J., Takahashi, H., Tanaka, T., Thayer, J. B., Thayer, J. G., Thompson, D. J., Tibaldo, L., Torres, D. F., Tosti, G., Tramacere, A., Usher, T. L., Vasileiou, V., Vilchez, N., Vitale, V., Waite, A. P., Wang, P., Winer, B. L., Wood, K. S., Yang, Z., Ylinen, T., and Ziegler, M.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: The high-frequency-peaked BL Lacertae object RGB J0710+591 was observed in the very high-energy (VHE; E > 100 GeV) wave band by the VERITAS array of atmospheric Cherenkov telescopes. The observations, taken between 2008 December and 2009 March and totaling 22.1 hr, yield the discovery of VHE gamma rays from the source. RGB J0710+591 is detected at a statistical significance of 5.5 standard deviations (5.5{\sigma}) above the background, corresponding to an integral flux of (3.9 +/- 0.8) x 10-12 cm-2 s-1 (3% of the Crab Nebula's flux) above 300 GeV. The observed spectrum can be fit by a power law from 0.31 to 4.6 TeV with a photon spectral index of 2.69 +/- 0.26stat +/- 0.20sys. These data are complemented by contemporaneous multiwavelength data from the Fermi Large Area Telescope, the Swift X-ray Telescope, the Swift Ultra-Violet and Optical Telescope, and the Michigan-Dartmouth-MIT observatory. Modeling the broadband spectral energy distribution (SED) with an equilibrium synchrotron self-Compton model yields a good statistical fit to the data. The addition of an external-Compton component to the model does not improve the fit nor brings the system closer to equipartition. The combined Fermi and VERITAS data constrain the properties of the high-energy emission component of the source over 4 orders of magnitude and give measurements of the rising and falling sections of the SED.
Published: 2010
Full Text: View/download PDF

7. Constraints on Cosmological Dark Matter Annihilation from the Fermi-LAT Isotropic Diffuse Gamma-Ray Measurement

Author: collaboration, The Fermi-LAT, Abdo, A. A., Ackermann, M., Ajello, M., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bouvier, A., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Burnett, T. H., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Carrigan, S., Casandjian, J. M., Cecchi, C., Elik, O. C., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Cutini, S., Dermer, C. D., de Angelis, A., de Palma, F., Digel, S. W., Silva, E. do Couto e, Drell, P. S., Dubois, R., Dumora, D., Edmonds, Y., Farnier, C., Favuzzi, C., Fegan, S. J., Focke, W. B., Fortin, P., Frailis, M., Fukazawa, Y., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giglietto, N., Giordano, F., Glanzman, T., Godfrey, G., Grove, J. E., Guillemot, L., Guiriec, S., Gustafsson, M., Hadasch, D., Harding, A. K., Horan, D., Hughes, R. E., Johnson, A. S., Johnson, W. N., Kamae, T., Katagiri, H., Kataoka, J., Kawai, N., Kerr, M., Knodlseder, J., Kuss, M., Lande, J., Latronico, L., Garde, M. Llena, Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Makeev, A., Mazziotta, M. N., McEnery, J. E., Meurer, C., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nolan, P. L., Norris, J. P., Nuss, E., Ohsugi, T., Omodei, N., Orlando, E., Ormes, J. F., Paneque, D., Panetta, J. H., Parent, D., Pelassa, V., Pepe, M., Pesce-Rollins, M., Piron, F., Raino, S., Rando, R., Reimer, A., Reimer, O., Reposeur, T., Rodriguez, A. Y., Roth, M., Sadrozinski, H. F. W., Sander, A., Parkinson, P. M. Saz, Scargle, J. D., Sellerholm, A., Sgro, C., Siskind, E. J., Smith, P. D., Spandre, G., Spinelli, P., Starck, J. L., Strickman, M. S., Suson, D. J., Takahashi, H., Tanaka, T., Thayer, J. B., Thayer, J. G., Torres, D. F., Uchiyama, Y., Usher, T. L., Vasileiou, V., Vilchez, N., Vitale, V., Waite, A. P., Wang, P., Winer, B. L., Wood, K. S., Ylinen, T., Zaharijas, G., and Ziegle, M.
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Phenomenology
Abstract: The first published Fermi large area telescope (Fermi-LAT) measurement of the isotropic diffuse gamma-ray emission is in good agreement with a single power law, and is not showing any signature of a dominant contribution from dark matter sources in the energy range from 20 to 100 GeV. We use the absolute size and spectral shape of this measured flux to derive cross section limits on three types of generic dark matter candidates: annihilating into quarks, charged leptons and monochromatic photons. Predicted gamma-ray fluxes from annihilating dark matter are strongly affected by the underlying distribution of dark matter, and by using different available results of matter structure formation we assess these uncertainties. We also quantify how the dark matter constraints depend on the assumed conventional backgrounds and on the Universe's transparency to high-energy gamma-rays. In reasonable background and dark matter structure scenarios (but not in all scenarios we consider) it is possible to exclude models proposed to explain the excess of electrons and positrons measured by the Fermi-LAT and PAMELA experiments. Derived limits also start to probe cross sections expected from thermally produced relics (e.g. in minimal supersymmetry models) annihilating predominantly into quarks. For the monochromatic gamma-ray signature, the current measurement constrains only dark matter scenarios with very strong signals., Comment: 29 pages, 7 figures, to be published in JCAP. Corresponding authors: Jan Conrad, Michael Gustafsson, Alexander Sellerholm, Gabrijela Zaharijas
Published: 2010
Full Text: View/download PDF

8. Fermi LAT Search for Photon Lines from 30 to 200 GeV and Dark Matter Implications

Author: The Fermi LAT Collaboration, Abdo, A. A., Ackermann, M., Ajello, M., Atwood, W. B., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Berenji, B., Bloom, E. D., Bonamente, E., Borgland, A. W., Bouvier, A., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Burnett, T. H., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Carrigan, S., Casandjian, J. M., Cecchi, C., Elik, O. C., Chekhtman, A., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Dermer, C. D., de Angelis, A., de Palma, F., Digel, S. W., Silva, E. do Couto e, Drell, P. S., Drlica-Wagner, A., Dubois, R., Dumora, D., Edmonds, Y., Essig, R., Farnier, C., Favuzzi, C., Fegan, S. J., Focke, W. B., Fortin, P., Frailis, M., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giglietto, N., Giordano, F., Glanzman, T., Godfrey, G., Grenier, I. A., Grove, J. E., Guillemot, L., Guiriec, S., Gustafsson, M., Hadasch, D., Harding, A. K., Horan, D., Hughes, R. E., Jackson, M. S., ohannesson, G. J ., Johnson, A. S., Johnson, R. P., Johnson, W. N., Kamae, T., Katagiri, H., Kataoka, J., Kawai, N., Kerr, M., dlseder, J. Kno ., Kuss, M., Lande, J., Latronico, L., Garde, M. Llena, Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Makeev, A., Mazziotta, M. N., McEnery, J. E., Meurer, C., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nolan, P. L., Norris, J. P., Nuss, E., Ohsugi, T., Omodei, N., Orlando, E., Ormes, J. F., Ozaki, M., Paneque, D., Panetta, J. H., Parent, D., Pelassa, V., Pepe, M., Pesce-Rollins, M., Piron, F., Rainó, S., Rando, R., Razzano, M., Reimer, A., Reimer, O., Reposeur, T., Ripken, J., Ritz, S., Rodriguez, A. Y., Roth, M., Sadrozinski, H. F. -W., Sander, A., Parkinson, P. M. Saz, Scargle, J. D., Schalk, T. L., Sellerholm, A., Sgró, C., Siskind, E. J., Smith, D. A., Smith, P. D., Spandre, G., Spinelli, P., Starck, J. -L., Strickman, M. S., Suson, D. J., Tajima, H., Takahashi, H., Tanaka, T., Thayer, J. B., Thayer, J. G., Tibaldo, L., Torres, D. F., Uchiyama, Y., Usher, T. L., Vasileiou, V., Vilchez, N., Vitale, V., Waite, A. P., Wang, P., Winer, B. L., Wood, K. S., Ylinen, T., and Ziegler, M.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Extragalactic Astrophysics, High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: Dark matter (DM) particle annihilation or decay can produce monochromatic $\gamma$-rays readily distinguishable from astrophysical sources. $\gamma$-ray line limits from 30 GeV to 200 GeV obtained from 11 months of Fermi Large Area Space Telescope data from 20-300 GeV are presented using a selection based on requirements for a $\gamma$-ray line analysis, and integrated over most of the sky. We obtain $\gamma$-ray line flux upper limits in the range $0.6-4.5\times 10^{-9}\mathrm{cm}^{-2}\mathrm{s}^{-1}$, and give corresponding DM annihilation cross-section and decay lifetime limits. Theoretical implications are briefly discussed., Comment: 6 pages, 1 figure. Accepted for publication by The Physical Review Letters
Published: 2010
Full Text: View/download PDF

9. Observations of Milky Way Dwarf Spheroidal galaxies with the Fermi-LAT detector and constraints on Dark Matter models

Author: Collaboration, Fermi-LAT, Abdo, A. A., Ackermann, M., Ajello, M., Atwood, W. B., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Berenji, B., Bloom, E. D., Bonamente, E., Borgland, A. W., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Burnett, T. H., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., de Angelis, A., de Palma, F., Digel, S. W., Silva, E. do Couto e, Drell, P. S., Drlica-Wagner, A., Dubois, R., Dumora, D., Farnier, C., Favuzzi, C., Fegan, S. J., Focke, W. B., Fortin, P., Frailis, M., Fukazawa, Y., Fusco, P., Gargano, F., Gehrels, N., Germani, S., Giebels, B., Giglietto, N., Giordano, F., Glanzman, T., Godfrey, G., Grenier, I. A., Grove, J. E., Guillemot, L., Guiriec, S., Gustafsson, M., Harding, A. K., Hays, E., Horan, D., Hughes, R. E., Jackson, M. S., Jeltema, T. E., Johannesson, G., Johnson, A. S., Johnson, R. P., Johnson, W. N., Kamae, T., Katagiri, H., Kataoka, J., Kerr, M., Knodlseder, J., Kuss, M., Lande, J., Latronico, L., Lemoine-Goumard, M., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Makeev, A., Mazziotta, M. N., McEnery, J. E., Meurer, C., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Moretti, E., Morselli, A., Moskalenko, I. V., Murgia, S., Nolan, P. L., Norris, J. P., Nuss, E., Ohsugi, T., Omodei, N., Orlando, E., Ormes, J. F., Paneque, D., Panetta, J. H., Parent, D., Pelassa, V., Pepe, M., Pesce-Rollins, M., Piron, F., Porter, T. A., Profumo, S., Raino, S., Rando, R., Razzano, M., Reimer, A., Reimer, O., Reposeur, T., Ritz, S., Rodriguez, A. Y., Roth, M., Sadrozinski, H. F. -W., Sander, A., Parkinson, P. M. Saz, Scargle, J. D., Schalk, T. L., Sellerholm, A., Sgro, C., Siskind, E. J., Smith, D. A., Smith, P. D., Spandre, G., Spinelli, P., Strickman, M. S., Suson, D. J., Takahashi, H., Takahashi, T., Tanaka, T., Thayer, J. B., Thayer, J. G., Thompson, D. J., Tibaldo, L., Torres, D. F., Tramacere, A., Uchiyama, Y., Usher, T. L., Vasileiou, V., Vilchez, N., Vitale, V., Waite, A. P., Wang, P., Winer, B. L., Wood, K. S., Ylinen, T., Ziegler, M., Bullock, James S., Kaplinghat, Manoj, and Martinez, Gregory D.
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Phenomenology
Abstract: We report on the observations of 14 dwarf spheroidal galaxies with the Fermi Gamma-Ray Space Telescope taken during the first 11 months of survey mode operations. The Fermi telescope provides a new opportunity to test particle dark matter models through the expected gamma-ray emission produced by pair annihilation of weakly interacting massive particles (WIMPs). Local Group dwarf spheroidal galaxies, the largest galactic substructures predicted by the cold dark matter scenario, are attractive targets for such indirect searches for dark matter because they are nearby and among the most extreme dark matter dominated environments. No significant gamma-ray emission was detected above 100 MeV from the candidate dwarf galaxies. We determine upper limits to the gamma-ray flux assuming both power-law spectra and representative spectra from WIMP annihilation. The resulting integral flux above 100 MeV is constrained to be at a level below around 10^-9 photons cm^-2 s^-1. Using recent stellar kinematic data, the gamma-ray flux limits are combined with improved determinations of the dark matter density profile in 8 of the 14 candidate dwarfs to place limits on the pair annihilation cross-section of WIMPs in several widely studied extensions of the standard model. With the present data, we are able to rule out large parts of the parameter space where the thermal relic density is below the observed cosmological dark matter density and WIMPs (neutralinos here) are dominantly produced non-thermally, e.g. in models where supersymmetry breaking occurs via anomaly mediation. The gamma-ray limits presented here also constrain some WIMP models proposed to explain the Fermi and PAMELA e^+e^- data, including low-mass wino-like neutralinos and models with TeV masses pair-annihilating into muon-antimuon pairs. (Abridged), Comment: 25 pages, 4 figures, accepted to ApJ, Corresponding authors: J. Cohen-Tanugi, C. Farnier, T.E. Jeltema, E. Nuss, and S. Profumo
Published: 2010
Full Text: View/download PDF

10. The Spectral Energy Distribution of Fermi bright blazars

Author: Abdo, A. A., Ackermann, M., Ajello, M., Axelsson, M., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Baughman, B. M., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Burnett, T. H., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cavazzuti, E., Cecchi, C., Celik, O., Charles, E., Chaty, S., Chekhtman, A., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Colafrancesco, S., Cominsky, L. R., Conrad, J., Costamante, L., Cutini, S., Dermer, C. D., de Angelis, A., de Palma, F., Digel, S. W., Silva, E. do Couto e, Drell, P. S., Dubois, R., Dumora, D., Farnier, C., Favuzzi, C., Fegan, S. J., Focke, W. B., Fortin, P., Frailis, M., Fuhrmann, L., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giebels, B., Giglietto, N., Giommi, P., Giordano, F., Glanzman, T., Godfrey, G., Grenier, I. A., Grove, J. E., Guillemot, L., Guiriec, S., Hadasch, D., Hanabata, Y., Harding, A. K., Hayashida, M., Hays, E., Healey, S. E., Horan, D., Hughes, R. E., Itoh, R., Jackson, M. S., Johannesson, G., Johnson, A. S., Johnson, W. N., Kadler, M., Kamae, T., Katagiri, H., Kataoka, J., Kawai, N., Kerr, M., Knodlseder, J., Kocian, M. L., Kuss, M., Lande, J., Latronico, L., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Makeev, A., Max-Moerbeck, W., Mazziotta, M. N., McConville, W., McEnery, J. E., Meurer, C., and Michelson, P. F.
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: (Abridged) We have conducted a detailed investigation of the broad-band spectral properties of the \gamma-ray selected blazars of the Fermi LAT Bright AGN Sample (LBAS). By combining our accurately estimated Fermi gamma-ray spectra with Swift, radio, infra-red, optical and other hard X-ray/gamma-ray data, collected within three months of the LBAS data taking period, we were able to assemble high-quality and quasi-simultaneous Spectral Energy Distributions (SED) for 48 LBAS blazars.The SED of these gamma-ray sources is similar to that of blazars discovered at other wavelengths, clearly showing, in the usual Log $\nu $ - Log $\nu$ F$_\nu$ representation, the typical broad-band spectral signatures normally attributed to a combination of low-energy synchrotron radiation followed by inverse Compton emission of one or more components. We have used these SEDs to characterize the peak intensity of both the low and the high-energy components. The results have been used to derive empirical relationships that estimate the position of the two peaks from the broad-band colors (i.e. the radio to optical and optical to X-ray spectral slopes) and from the gamma-ray spectral index. Our data show that the synchrotron peak frequency $\nu_p^S$ is positioned between 10$^{12.5}$ and 10$^{14.5}$ Hz in broad-lined FSRQs and between $10^{13}$ and $10^{17}$ Hz in featureless BL Lacertae objects.We find that the gamma-ray spectral slope is strongly correlated with the synchrotron peak energy and with the X-ray spectral index, as expected at first order in synchrotron - inverse Compton scenarios. However, simple homogeneous, one-zone, Synchrotron Self Compton (SSC) models cannot explain most of our SEDs, especially in the case of FSRQs and low energy peaked (LBL) BL Lacs. (...), Comment: 85 pages, 38 figures, submitted to ApJ
Published: 2009
Full Text: View/download PDF

11. DIFFERENTIAL TIMING OF WILSON'S WARBLER MIGRATION IN ALASKA

Author: Benson, Anna-Marie, Andres, Brad A, Johnson, W N, Savage, Susan, Sharbaugh, Susan M, and BioStor
Published: 2006

12. Multifrequency Observations of the Virgo Blazars 3C 273 and 3C 279 in CGRO Cycle 8

Author: Collmar, W., Benlloch, S., Grove, J. E., Hartman, R. C., Heindl, W. A., Kraus, A., Teraesranta, H., Villata, M., Bennett, K., Bloemen, H., Johnson, W. N., Krichbaum, T. P., Raiteri, C. M., Ryan, J., Sobrito, G., Schoenfelder, V., Williams, O. R., and Wilms, J.
Subjects: Astrophysics
Abstract: We report first observational results of multifrequency campaigns on the prominent Virgo blazars 3C 273 and 3C 279 which were carried out in January and February 1999. Both blazars are detected from radio to gamma-ray energies. We present the measured X- to gamma-ray spectra of both sources, and for 3C 279 we compare the 1999 broad-band (radio to gamma-ray) spectrum to measured previous ones., Comment: 5 pages including 3 figures, latex2e, to appear in: 'Proc. of the 5th Compton Symposium', AIP, in press
Published: 2000
Full Text: View/download PDF

13. The USA X-ray Timing Experiment

Author: Ray, P. S., Wood, K. S., Fritz, G., Hertz, P., Kowalski, M., Johnson, W. N., Lovellette, M. N., Wolff, M. T., Yentis, D., Bandyopadhyay, R. M., Bloom, E. D., Giebels, B., Godfrey, G., Reilly, K., Parkinson, P. Saz, Shabad, G., Michelson, P., Roberts, M., Leahy, D. A., Cominsky, L., Scargle, J., Beall, J., Chakrabarty, D., and Kim, Y.
Subjects: Astrophysics
Abstract: The USA Experiment is a new X-ray timing experiment with large collecting area and microsecond time resolution capable of conducting a broad program of studies of galactic X-ray binaries. USA is one of nine experiments aboard the Advanced Research and Global Observation Satellite which was launched February 23, 1999. USA is a collimated proportional counter X-ray telescope with about 1000 cm$^2$ of effective area per detector with two detectors sensitive to photons in the energy range 1-15 keV. A unique feature of USA is that photon events are time tagged by reference to an onboard GPS receiver allowing precise absolute time and location determination. We will present an overview of the USA instrument, capabilities, and scientific observing plan as well as the current status of the instrument., Comment: Proceedings of X-ray Astronomy 1999, Bologna, 10 pages, 3 figures
Published: 1999

14. Radiation mechanisms and geometry of Cygnus X-1 in the soft state

Author: Gierlinski, M., Zdziarski, A. A., Poutanen, J., Coppi, P. S., Ebisawa, K., and Johnson, W. N.
Subjects: Astrophysics
Abstract: We present X-ray/gamma-ray spectra of Cyg X-1 observed during the transition from the hard to the soft state and in the soft state by ASCA, RXTE and OSSE in 1996 May and June. The spectra consist of a dominant soft component below ~2 keV and a power-law-like continuum extending to at least ~800 keV. We interpret them as emission from an optically-thick, cold accretion disc and from an optically-thin, non-thermal corona above the disc. A fraction f ~ 0.6 of total available power is dissipated in the corona. We model the soft component by multi-colour blackbody disc emission taking into account the torque-free inner-boundary condition. If the disc extends down to the minimum stable orbit, the ASCA/RXTE data yield the most probable black hole mass of about 10 solar masses and an accretion rate about 0.5 L_E/c^2, locating Cyg X-1 in the soft state in the upper part of the stable, gas-pressure dominated, accretion-disc solution branch. The spectrum of the corona is well modelled by repeated Compton scattering of seed photons from the disc off electrons with a hybrid, thermal/non-thermal distribution. The electron distribution can be characterized by a Maxwellian with an equilibrium temperature of kT ~ 30--50 keV and a Thomson optical depth of ~0.3 and a quasi-power-law tail. The compactness of the corona is between 2 and 7, and a presence of a significant population of electron-positron pairs is ruled out. We find strong signatures of Compton reflection from a cold and ionized medium, presumably an accretion disc, with an apparent reflector solid angle ~0.5--0.7. The reflected continuum is accompanied by a broad iron K-alpha line., Comment: 18 pages, 12 figures, 2 landscape tables in a separate file. Accepted to MNRAS
Published: 1999
Full Text: View/download PDF

15. Beam Test of Gamma-ray Large Area Space Telescope Components

Author: Atwood, W. B., Ritz, S., Anthony, P., Bloom, E. D., Bosted, P. E., Bourotte, J., Chaput, C., Chen, X., Chenette, D. L., Engovatov, D., Erickson, R., Fieguth, T., Fleury, P., Gearhart, R., Godfrey, G., Grove, J. E., Hernando, J. A., Hirayama, M., Jaggar, S., Johnson, R. P., Johnson, W. N., Jones, B. B., Kroeger, W., Lin, Y. C., Meetre, C., Michelson, P. F., Milne, P. A., Moiseev, A., Nolan, P., Norris, J. P., Oreglia, M., Ormes, J. F., Phlips, B. F., Pocar, A., Sadrozinski, H. F. -W., Szalata, Z., Thompson, D. J., and Tompkins, W. F.
Subjects: Physics - Instrumentation and Detectors, Physics - Space Physics
Abstract: A beam test of GLAST (Gamma-ray Large Area Space Telescope) components was performed at the Stanford Linear Accelerator Center in October, 1997. These beam test components were simple versions of the planned flight hardware. Results on the performance of the tracker, calorimeter, and anti-coincidence charged particle veto are presented., Comment: 39 pages, 21 figures
Published: 1999
Full Text: View/download PDF

16. Real-time Likelihood Methods for Improved γ-Ray Transient Detection and Localization

Author: Kerr, M., primary, Duvall, W., additional, Johnson, W. N., additional, Woolf, R. S., additional, Grove, J. E., additional, and Kim, H., additional
Published: 2023
Full Text: View/download PDF

17. Gamma-Ray Spectral States of Galactic Black Hole Candidates

Author: Grove, J. E., Johnson, W. N., Kroeger, R. A., McNaron-Brown, K., Skibo, J. G., and Phlips, B. F.
Subjects: Astrophysics
Abstract: OSSE has observed seven transient black hole candidates: GRO J0422+32, GX339-4, GRS 1716-249, GRS 1009-45, 4U 1543-47, GRO J1655-40, and GRS 1915+105. Two gamma-ray spectral states are evident and, based on a limited number of contemporaneous X-ray and gamma-ray observations, these states appear to be correlated with X-ray states. The former three objects show hard spectra below 100 keV (photon number indices Gamma < 2) that are exponentially cut off with folding energy ~100 keV, a spectral form that is consistent with thermal Comptonization. This "breaking gamma-ray state" is the high-energy extension of the X-ray low, hard state. In this state, the majority of the luminosity is above the X-ray band, carried by photons of energy ~100 keV. The latter four objects exhibit a "power-law gamma-ray state" with a relatively soft spectral index (Gamma ~ 2.5-3) and no evidence for a spectral break. For GRO J1655-40, the lower limit on the break energy is 690 keV. GRS 1716-249 exhibits both spectral states, with the power-law state having significantly lower gamma-ray luminosity. The power-law gamma-ray state is associated with the presence of a strong ultrasoft X-ray excess (kT ~ 1 keV), the signature of the X-ray high, soft (or perhaps very high) state. The physical process responsible for the unbroken power law is not well understood, although the spectra are consistent with bulk-motion Comptonization in the convergent accretion flow., Comment: 27 pages, 3 figures, uses aaspp.sty and psfig.sty
Published: 1998
Full Text: View/download PDF

18. Thermal/non-thermal model of Cyg X-1 in the soft state

Author: Gierlinski, Marek, Zdziarski, Andrzej A., Coppi, Paolo S., Poutanen, Juri, Ebisawa, Ken, and Johnson, W. N.
Subjects: Astrophysics
Abstract: We analyze X-ray/gamma-ray observations of Cyg X-1 in the soft state. We find the hybrid thermal/non-thermal model fits the data very well. The significant contribution from the non-thermal electrons is required to account for the observed power law extending without a break to at least 800 keV. The presence of electron-positron pairs in the hot source is unlikely. We propose the geometry in which a cold accretion disk, surrounded by a hot corona, extends down to the last stable orbit. At the observed accretion rate the corona ensures the stability of the cold disk., Comment: 4 pages, 3 figures, Proceedings of the Conference "The Active X-ray Sky", Rome, 21-24 October 1997
Published: 1997
Full Text: View/download PDF

19. Broad-band continuum and variability of NGC 5548

Author: Magdziarz, P., Blaes, O. M., Zdziarski, A. A., Johnson, W. N., and Smith, D. A.
Subjects: Astrophysics
Abstract: We analyze a composite broad-band optical/UV/Xgamma-ray spectrum of the Seyfert 1 galaxy NGC 5548. The spectrum consists of an average of simultaneous optical/IUE/Ginga observations accompanied by ROSAT and GRO/OSSE data from non-simultaneous observations. We show that the broad-band continuum is inconsistent with simple disk models extending to the soft X-rays. Instead, the soft-excess is well described by optically thick, low temperature, thermal Comptonization which may dominate the entire big blue bump. This might explain the observed tight UV/soft X-ray variability correlation and absence of a Lyman edge in this object. However, the plasma parameters inferred by the spectrum need stratification in optical depth and/or temperature to prevent physical inconsistency. The optical/UV/soft X-ray component contributes about half of the total source flux. The spectral variations of the soft-excess are consistent with that of the UV and argue that the components are closely related. The overall pattern of spectral variability suggests variations of the source geometry, and shows the optical/UV/soft X-ray component to be harder when brighter, while the hard X-ray component is softer when brighter., Comment: 5 pages, 3 figures, LaTex, using AIP macro, to appear in Proceedings of "4th Compton Symposium", April 27-30, 1997, Williamsburg, Virginia, USA
Published: 1997
Full Text: View/download PDF

20. Multiwavelength Observations of a Flare from Markarian 501

Author: Catanese, M., Bradbury, S. M., Breslin, A. C., Buckley, J. H., Carter-Lewis, D. A., Cawley, M. F., Dermer, C. D., Fegan, D. J., Finley, J. P., Gaidos, J. A., Hillas, A. M., Johnson, W. N., Krennrich, F., Lamb, R. C., Lessard, R. W., Macomb, D. J., McEnery, J. E., Moriarty, P., Quinn, J., Rodgers, A. J., Rose, H. J., Samuelson, F. W., Sembroski, G. H., Srinivasan, R., Weekes, T. C., and Zweerink, J.
Subjects: Astrophysics
Abstract: We present multiwavelength observations of the BL Lacertae object Markarian 501 (Mrk 501) in 1997 between April 8 and April 19. Evidence of correlated variability is seen in very high energy (VHE, E > 350 GeV) gamma-ray observations taken with the Whipple Observatory gamma-ray telescope, data from the Oriented Scintillation Spectrometer Experiment of the Compton Gamma-Ray Observatory, and quicklook results from the All-Sky Monitor of the Rossi X-ray Timing Explorer while the Energetic Gamma-Ray Experiment Telescope did not detect Mrk 501. Short term optical correlations are not conclusive but the U-band flux observed with the 1.2m telescope of the Whipple Observatory was 10% higher than in March. The average energy output of Mrk 501 appears to peak in the 2 keV to 100 keV range suggesting an extension of the synchrotron emission to at least 100 keV, the highest observed in a blazar and ~100 times higher than that seen in the other TeV-emitting BL Lac object, Mrk 421. The VHE gamma-ray flux observed during this period is the highest ever detected from this object. The VHE gamma-ray energy output is somewhat lower than the 2-100 keV range but the variability amplitude is larger. The correlations seen here do not require relativistic beaming of the emission unless the VHE spectrum extends to >5 TeV., Comment: 10 pages, 2 figures, accepted for publication in ApJ Letters
Published: 1997
Full Text: View/download PDF

21. OSSE Observations of the Soft Gamma Ray Continuum from the Galactic Plane at Longitude 95 Degrees

Author: Skibo, J. G., Johnson, W. N., Kurfess, J. D., Kinzer, R. L., Jung, G., Grove, J. E., Purcell, W. R., Ulmer, M. P., Gehrels, N., and Tueller, J.
Subjects: Astrophysics
Abstract: We present the results of OSSE observations of the soft gamma ray continuum emission from the Galactic plane at longitude 95 degrees. Emission is detected between 50 and 600 keV where the spectrum is fit well by a power law with photon index -2.6+-0.3 and flux (4.0+-0.5) 10^{-2} photons/s/cm^2/rad/MeV at 100 keV. This spectral shape in this range is similar to that found for the continuum emission from the inner Galaxy but the amplitude is lower by a factor of four. This emission is either due to unresolved and previously unknown point sources or it is of diffuse origin, or a combination of the two. Simultaneous observations with OSSE and smaller field of view instruments operating in the soft gamma ray energy band, such as XTE or SAX, would help resolve this issue. If it is primarily diffuse emission due to nonthermal electron bremsstrahlung, as is the >1 MeV Galactic ridge continuum, then the power in low energy cosmic ray electrons exceeds that of the nuclear component of the cosmic rays by an order of magnitude. This would have profound implications for the origin of cosmic rays and the energetics of the interstellar medium. Alternatively, if the emission is diffuse and thermal, then there must be a component of the interstellar medium at temperatures near 10^9 K., Comment: 11 pages, Latex, requires AASTEX macros and psfig.tex, 2 postscript figures, Accepted for publication in the Astrophysical Journal Letters
Published: 1997
Full Text: View/download PDF

22. Skymapping with OSSE via the Mean Field Annealing Pixon Technique

Author: Dixon, D. D., Tumer, T. O., Zych, A. D., Cheng, L. X., Johnson, W. N., Kurfess, J. D., Pina, R. K., Puetter, R. C., Purcell, W. R., and Wheaton, Wm. A.
Subjects: Astrophysics
Abstract: We present progress toward using scanned OSSE observations for mapping and sky survey work. To this end, we have developed a technique for detecting pointlike sources of unknown number and location, given that they appear in a background which is relatively featureless or which can be modeled. The technique, based on the newly developed concept and mean field annealing, is described, with sample reconstructions of data from the OSSE Virgo Survey. The results demonstrate the capability of reconstructing source information without any a priori information about the number and/or location of pointlike sources in the field-of-view., Comment: 15 pages, 4 Postscript figs, AASTeX, uses psfig and epsf. To appear in the Astrophysical Journal, vol. 484
Published: 1997
Full Text: View/download PDF

23. An Intense Gamma-Ray Flare of PKS1622-297

Author: Mattox, J. R., Wagner, S. J., Malkan, M., McGlynn, T. A., Schachter, J. F., Grove, J. E., Johnson, W. N., and Kurfess, J. D.
Subjects: Astrophysics
Abstract: We report the observation by the Compton Gamma Ray Observatory of a spectacular flare of radio source PKS 1622-297. A peak flux of 17E-6 cm^-2 s^-1 (E > 100 MeV) was observed. The corresponding isotropic luminosity is 2.9E49 erg/s. We find that PKS 1622-297 exhibits gamma-ray intra-day variability. A flux increase by a factor of at least 3.6 was observed to occur in less than 7.1 hours (with 99% confidence). Assuming an exponential rise, the corresponding doubling time is less than 3.8 hours. A significant flux decrease by a factor of ~2 in 9.7 hours was also observed. Without beaming, the rapid flux change and large isotropic luminosity are inconsistent with the Elliot-Shapiro condition (assuming that gas accretion is the immediate source of power for the gamma-rays). This inconsistency suggests that the gamma-ray emission is beamed. A minimum Doppler factor of 8.1 is implied by the observed lack of pair-production opacity (assuming x-rays are emitted co-spatially with the gamma-rays). Simultaneous observation by EGRET and OSSE finds a spectrum adequately fit by a power law with photon index of -1.9. Although the significance is not sufficient to establish this beyond doubt, the high-energy gamma-ray spectrum appears to evolve from hard to soft as a flare progresses., Comment: 14 pages, 4 figures, 1 table
Published: 1996
Full Text: View/download PDF

24. The average X-ray/gamma-ray spectrum of radio-quiet Seyfert 1s

Author: Gondek, D., Zdziarski, A. A., Johnson, W. N., George, I. M., McNaron-Brown, K., Magdziarz, P., Smith, D., and Gruber, E.
Subjects: Astrophysics
Abstract: We have obtained the average 1--500 keV spectrum of radio-quiet Seyfert 1s using data from EXOSAT, Ginga, HEAO, and GRO/OSSE. The spectral fit to the combined average EXOSAT and OSSE data is fully consistent with that for Ginga and OSSE, confirming results from an earlier Ginga/OSSE sample. The average spectrum is well-fitted by a power-law X-ray continuum with an energy spectral index of $\alpha \simeq 0.9$ moderately absorbed by an ionized medium and with a Compton reflection component. A high-energy cutoff (or a break) in the the power-law component at a few hundred keV or more is required by the data. We also show that the corresponding average spectrum from HEAO A1 and A4 is fully compatible with that obtained from EXOSAT, Ginga and OSSE. These results confirm that the apparent discrepancy between the results of Ginga (with $\alpha \simeq 0.9$) and the previous results of EXOSAT and HEAO (with $\alpha \simeq 0.7$) is indeed due to ionized absorption and Compton reflection first taken into account for Ginga but not for the previous missions. Also, our results confirm that the Seyfert-1 spectra are on average cut off in gamma-rays at energies of at least a few hundred keV, not at $\sim 40$ keV (as suggested earlier by OSSE data alone). The average spectrum is compatible with emission from either an optically-thin relativistic thermal plasma in a disk corona, or with a nonthermal plasma with a power-law injection of relativistic electrons., Comment: 7 pages, 3 Postscript figures, MNRAS accepted
Published: 1996
Full Text: View/download PDF

25. Broad-band gamma-ray and X-ray spectra of NGC 4151 and their implications for physical processes and geometry

Author: Zdziarski, A. A., Johnson, W. N., and Magdziarz, P.
Subjects: Astrophysics
Abstract: We study gamma-ray observations of NGC 4151 by GRO/OSSE contemporaneous with X-ray observations by ROSAT and Ginga in 1991 June and with ASCA in 1993 May. The spectra are well modeled by thermal Comptonization and a dual neutral absorber. We also find, for the first time for NGC 4151, a Compton-reflection spectral component in the Ginga/OSSE data. The OSSE spectra of those and other observations of NGC 4151 are statistically undistinguishable from the average OSSE spectrum of radio-quiet Seyfert 1s. NGC 4151 observed in 1991 and 1993 has the intrinsic X-ray/gamma-ray spectrum typical for Seyfert 1s, and the main property distinguishing it from other Seyfert 1s is a large absorbing column of $\sim 10^{23}$ cm$^{-2}$. We find no evidence for a strong, broad and redshifted, Fe K$\alpha$ line component in the ASCA spectrum of 1993 May. On the other hand, we confirm previous studies in that archival X-ray data do imply strong intrinsic X-ray variability and hardness of the intrinsic spectrum in low X-ray states. An observed softening of the intrinsic X-ray spectrum with the increasing flux implies variability in gamma-rays weaker than in X-rays, which agrees with the 100 keV flux changing only within a factor of 2 in archival OSSE and Granat/SIGMA observations. The relative hardness of the intrinsic X-ray spectrum rules out the homogeneous hot corona/cold disk model for this source. Instead, the hot plasma has to subtend a small solid angle as seen from the source of UV radiation. If the hot plasma is purely thermal, it consists of electrons rather than $e^+e^-$ pairs. On the other hand, the plasma can be pair-dominated if a small fraction of the power is nonthermal., Comment: 15 pages, 8 Postscript figures, MNRAS accepted
Published: 1996
Full Text: View/download PDF

26. Selection of Post-Fire Seres by Lynx and Snowshoe Hares in the Alaskan Taiga

Author: Paragi, Thomas F., Johnson, W. N., Katnik, Donald D., and Magoun, Audrey J.
Published: 1997
Full Text: View/download PDF

27. Germanium Orthogonal Strip Detectors with Amorphous-Semiconductor Contacts

Author: Luke, P N, Amman, M, Phlips, B F, Johnson, W N, and Kroeger, R A
Published: 1999

28. Range expansion and hosts of Ctenophthalmus pseudagyrtes Baker (Siphonaptera: Ctenophthalmidae) in central Alaska

Author: Haas, G E, Wilson, N, Kucera, J R, Osborne, T O, Whitman, J S, Johnson, W N, and BioStor
Published: 2010

29. Fermi-LAT Observations of the Gamma-Ray Burst GRB 130427A

Author: Ackermann, M., Ajello, M., Asano, K., Atwood, W. B., Axelsson, M., Baldini, L., Ballet, J., Barbiellini, G., Baring, M. G., Bastieri, D., Bechtol, K., Bellazzini, R., Bissaldi, E., Bonamente, E., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Burgess, J. Michael, Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Cecchi, C., Chaplin, V., Charles, E., Chekhtman, A., Cheung, C. C., Chiang, J., Chiaro, G., Ciprini, S., Claus, R., Cleveland, W., Cohen-Tanugi, J., Collazzi, A., Cominsky, L. R., Connaughton, V., Conrad, J., Cutini, S., D'Ammando, F., de Angelis, A., DeKlotz, M., de Palma, F., Dermer, C. D., Desiante, R., Diekmann, A., Di Venere, L., Drell, P. S., Drlica-Wagner, A., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Finke, J., Fitzpatrick, G., Focke, W. B., 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, I. A., Grove, J. E., Gruber, D., Guiriec, S., Hadasch, D., Hanabata, Y., Harding, A. K., Hayashida, M., Hays, E., Horan, D., Hughes, R. E., Inoue, Y., Jogler, T., Jóhannesson, G., Johnson, W. N., Kawano, T., Knödlseder, J., Kocevski, D., Kuss, M., Lande, J., Larsson, S., Latronico, L., Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., Mayer, M., Mazziotta, M. N., McEnery, J. E., Michelson, P. F., Mizuno, T., Moiseev, A. A., Monzani, M. E., Moretti, E., Morselli, A., Moskalenko, I. V., Murgia, S., Nemmen, R., Nuss, E., Ohno, M., Ohsugi, T., Okumura, A., Omodei, N., Orienti, M., Paneque, D., Pelassa, V., Perkins, J. S., Pesoe-Rollins, M., Petrosian, V., Piron, F., Pivato, G., Porter, T. A., Racusin, J. L, Rainò, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Ritz, S., Roth, M., Ryde, F., Sartori, A., Parkinson, P. M. Saz, Scargle, J. D., Schulz, A., Sgrò, C., Siskind, E. J., Sonbas, E., Spandre, G., Spinelli, P., Tajima, H., Takahashi, H., Thayer, J. G., Thayer, J. A., Thompson, D. J., Tibaldo, L., Tinivella, M., Torres, D. F., Tosti, G., Troja, E., Usher, T. L., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Winer, B. L., Wood, K. S., Yamazaki, R., Younes, G., Yu, H.-F., Zhu, S. J., Bhat, P. N., Briggs, M. S., Byrne, D., Foley, S., Goldstein, A., Jenke, P., Kippen, R. M., Kouveliotou, C., McBreen, S., Meegan, C., Paciesas, W. S., Preece, R., Rau, A., Tierney, D., van der Horst, A. J., von Kienlin, A., Wilson-Hodge, C., Xiong, S., Cusumano, G., La Parola, V., and Cummings, J. R.
Published: 2014
Full Text: View/download PDF

30. Gamma-Ray Emission from the Shell of Supernova Remnant W44 Revealed by the Fermi LAT

Author: Abdo, A. A., Ackermann, M., Ajello, M., Baldini, L., Ballet, J., Barbiellini, G., Baring, M. G., Bastieri, D., Baughman, B. M., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Burnett, T. H., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Çelik, Ö., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cognard, I., Cohen-Tanugi, J., Cominsky, L. R., Conrad, J., Cutini, S., Dermer, C. D., de Angelis, A., de Palma, F., Digel, S. W., do Couto e Silva, E., Drell, P. S., Dubois, R., Dumora, D., Espinoza, C., Farnier, C., Favuzzi, C., Fegan, S. J., Focke, W. B., Fortin, P., Frailis, M., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giavitto, G., Giebels, B., Giglietto, N., Giordano, F., Glanzman, T., Godfrey, G., Grenier, I. A., Grondin, M.-H., Grove, J. E., Guillemot, L., Guiriec, S., Hanabata, Y., Harding, A. K., Hayashida, M., Hays, E., Hughes, R. E., Jackson, M. S., Jóhannesson, G., Johnson, A. S., Johnson, T. J., Johnson, W. N., Kamae, T., Katagiri, H., Kataoka, J., Katsuta, J., Kawai, N., Kerr, M., Knödlseder, J., Kocian, M. L., Kramer, M., Kuss, M., Lande, J., Latronico, L., Lemoine-Goumard, M., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Lyne, A. G., Madejski, G. M., Makeev, A., Mazziotta, M. N., McEnery, J. E., Meurer, C., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nakamori, T., Nolan, P. L, Norris, J. P., Noutsos, A., Nuss, E., Ohsugi, T., Omodei, N., Orlando, E., Ormes, J. F., Paneque, D., Parent, D., Pelassa, V., Pepe, M., Pesce-Rollins, M., Piron, F., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Reimer, A., Reimer, O., Reposeur, T., Rochester, L. S., Rodriguez, A. Y., Romani, R. W., Roth, M., Ryde, F., Sadrozinski, H. F.-W., Sanchez, D., Sander, A., Parkinson, P. M. Saz, Scargle, J. D., Sgrò, C., Siskind, E. J., Smith, D. A., Smith, P. D., Spandre, G., Spinelli, P., Stappers, B. W., Stecker, F. W., Strickman, M. S., Suson, D. J., Tajima, H., Takahashi, H., Takahashi, T., Thayer, J. B., Thayer, J. G., Theureau, G., Thompson, D. J., Tibaldo, L., Tibolla, O., Torres, D. F., Tosti, G., Tramacere, A., Uchiyama, Y., Usher, T. L., Vasileiou, V., Venter, C., Vilchez, N., Vitale, V., Waite, A. P., Wang, P., Winer, B. L., Wood, S., Yamazaki, R., Ylinen, T., and Ziegler, M.
Published: 2010
Full Text: View/download PDF

31. A Population of Gamma-Ray Millisecond Pulsars Seen with the Fermi Large Area Telescope

Author: Abdo, A. A., Ackermann, M., Ajello, M., Atwood, W. B., Axelsson, M., Baldini, L., Ballet, J., Barbiellini, G., Baring, M. G., Bastieri, D., Baughman, B. M., Bechtol, K., Bellazzini, R., Berenji, B., Bignami, G. F., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Burnett, T. H., Caliandro, G. A., Cameron, R. A., Camilo, F., Caraveo, P. A., Carlson, P., Casandjian, J. M., Cecchi, C., Çelik, Ö., Charles, E., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cognard, I., Cohen-Tanugi, J., Cominsky, L. R., Conrad, J., Corbet, R., Cutini, S., Dermer, C. D., Desvignes, G., de Angelis, A., de Luca, A., de Palma, F., Digel, S. W., Dormody, M., Silva, E. do Couto e, Drell, P. S., Dubois, R., Dumora, D., Edmonds, Y., Farnier, C., Favuzzi, C., Fegan, S. J., Focke, W. B., Frailis, M., Freire, P. C. C., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giebels, B., Giglietto, N., Giordano, F., Glanzman, T., Godfrey, G., Grenier, I. A., Grondin, M. H., Grove, J. E., Guillemot, L., Guiriec, S., Hanabata, Y., Harding, A. K., Hayashida, M., Hays, E., Hobbs, G., Hughes, R. E., Jóhannesson, G., Johnson, A. S., Johnson, R. P., Johnson, T. J., Johnson, W. N., Johnston, S., Kamae, T., Katagiri, H., Kataoka, J., Kawai, N., Kerr, M., Knödlseder, J., Kocian, M. L., Kramer, M., Kuss, M., Lande, J., Latronico, L., Lemoine-Goumard, M., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Makeev, A., Manchester, R. N., Marelli, M., Mazziotta, M. N., McConville, W., McEnery, J. E., McLaughlin, M. A., Meurer, C., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nolan, P. L., Norris, J. P., Nuss, E., Ohsugi, T., Omodei, N., Orlando, E., Ormes, J. F., Paneque, D., Panetta, J. H., Parent, D., Pelassa, V., Pepe, M., Pesce-Rollins, M., Piron, F., Porter, T. A., Rainò, S., Rando, R., Ransom, S. M., Ray, P. S., Razzano, M., Rea, N., Reimer, A., Reimer, O., Reposeur, T., Ritz, S., Rochester, L. S., Rodriguez, A. Y., Romani, R. W., Roth, M., Ryde, F., Sadrozinski, H. F. W., Sanchez, D., Sander, A., Parkinson, P. M. Saz, Scargle, J. D., Schalk, T. L., Sgrò, C., Siskind, E. J., Smith, D. A., Smith, P. D., Spandre, G., Spinelli, P., Stappers, B. W., Starck, J. L., Striani, E., Strickman, M. S., Suson, D. J., Tajima, H., Takahashi, H., Tanaka, T., Thayer, J. B., Thayer, J. G., Theureau, G., Thompson, D. J., Thorsett, S. E., Tibaldo, L., Torres, D. F., Tosti, G., Tramacere, A., Uchiyama, Y., Usher, T. L., Van Etten, A., Vasileiou, V., Venter, C., Vilchez, N., Vitale, V., Waite, A. P., Wallace, E., Wang, P., Watters, K., Webb, N., Weltevrede, P., Winer, B. L., Wood, K. S., Ylinen, T., and Ziegler, M.
Published: 2009
Full Text: View/download PDF

32. Detection of 16 Gamma-Ray Pulsars through Blind Frequency Searches Using the Fermi LAT

Author: Abdo, A. A., Ackermann, M., Ajello, M., Anderson, B., Atwood, W. B., Axelsson, M., Baldini, L., Ballet, J., Barbiellini, G., Baring, M. G., Bastieri, D., Baughman, B. M., Bechtol, K., Bellazzini, R., Berenji, B., Bignami, G. F., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Burnett, T. H., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Çelik, Ö., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Cutini, S., Dermer, C. D., de Angelis, A., de Luca, A., de Palma, F., Digel, S. W., Dormody, M., Silva, E. do Couto e, Drell, P. S., Dubois, R., Dumora, D., Farnier, C., Favuzzi, C., Fegan, S. J., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giebels, B., Giglietto, N., Giommi, P., Giordano, F., Glanzman, T., Godfrey, G., Grenier, I. A., Grondin, M.-H., Grove, J. E., Guillemot, L., Guiriec, S., Gwon, C., Hanabata, Y., Harding, A. K., Hayashida, M., Hays, E., Hughes, R. E., Jóhannesson, G., Johnson, R. P., Johnson, T. J., Johnson, W. N., Kamae, T., Katagiri, H., Kataoka, J., Kawai, N., Kerr, M., Knödlseder, J., Kocian, M. L., Kuss, M., Lande, J., Latronico, L., Lemoine-Goumard, M., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Makeev, A., Marelli, M., Mazziotta, M. N., McConville, W., McEnery, J. E., Meurer, C., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nolan, P. L., Norris, J. P., Nuss, E., Ohsugi, T., Omodei, N., Orlando, E., Ormes, J. F., Paneque, D., Parent, D., Pelassa, V., Pepe, M., Pesce-Rollins, M., Pierbattista, M., Piron, F., Porter, T. A., Primack, J. R., Rainò, S., Rando, R., Ray, P. S., Razzano, M., Rea, N., Reimer, A., Reimer, O., Reposeur, T., Ritz, S., Rochester, L. S., Rodriguez, A. Y., Romani, R. W., Ryde, F., Sadrozinski, H. F.-W., Sanchez, D., Sander, A., Parkinson, P. M. Saz, Scargle, J. D., Sgrò, C., Siskind, E. J., Smith, D. A., Smith, P. D., Spandre, G., Spinelli, P., Starck, J.-L., Strickman, M. S., Suson, D. J., Tajima, H., Takahashi, H., Takahashi, T., Tanaka, T., Thayer, J. G., Thompson, D. J., Tibaldo, L., Tibolla, O., Torres, D. F., Tosti, G., Tramacere, A., Uchiyama, Y., Usher, T. L., Van Etten, A., Vasileiou, V., Vilchez, N., Vitale, V., Waite, A. P., Wang, P., Watters, K., Winer, B. L., Wolff, M. T., Wood, K. S., Ylinen, T., and Ziegler, M.
Published: 2009
Full Text: View/download PDF

33. Detection of High-Energy Gamma-Ray Emission from the Globular Cluster 47 Tucanae with Fermi

Author: Abdo, A. A., Ackermann, M., Ajello, M., Atwood, W. B., Axelsson, M., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Baughman, B. M., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Burnett, T. H., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Çelik, Ö., Charles, E., Chaty, S., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Cutini, S., Dermer, C. D., de Palma, F., Digel, S. W., Dormody, M., Silva, E. do Couto e, Drell, P. S., Dubois, R., Dumora, D., Farnier, C., Favuzzi, C., Fegan, S. J., Focke, W. B., Frailis, M., Fukazawa, Y., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giebels, B., Giglietto, N., Giordano, F., Glanzman, T., Godfrey, G., Grenier, I. A., Grove, J. E., Guillemot, L., Guiriec, S., Hanabata, Y., Harding, A. K., Hayashida, M., Hays, E., Horan, D., Hughes, R. E., Jóhannesson, G., Johnson, A. S., Johnson, R. P., Johnson, T. J., Johnson, W. N., Kamae, T., Katagiri, H., Kawai, N., Kerr, M., Knödlseder, J., Kuehn, F., Kuss, M., Lande, J., Latronico, L., Lemoine-Goumard, M., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Makeev, A., Mazziotta, M. N., McConville, W., McEnery, J. E., Meurer, C., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nolan, P. L., Norris, J. P., Nuss, E., Ohsugi, T., Omodei, N., Orlando, E., Ormes, J. F., Paneque, D., Panetta, J. H., Parent, D., Pelassa, V., Pepe, M., Pierbattista, M., Piron, F., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Rea, N., Reimer, A., Reimer, O., Reposeur, T., Ritz, S., Rochester, L. S., Rodriguez, A. Y., Romani, R. W., Roth, M., Ryde, F., Sadrozinski, H. F.-W., Sanchez, D., Sander, A., Parkinson, P. M. Saz, Sgrò, C., Smith, D. A., Smith, P. D., Spandre, G., Spinelli, P., Starck, J.-L., Strickman, M. S., Suson, D. J., Tajima, H., Takahashi, H., Tanaka, T., Thayer, J. B., Thayer, J. G., Thompson, D. J., Tibaldo, L., Torres, D. F., Tosti, G., Tramacere, A., Uchiyama, Y., Usher, T. L., Vasileiou, V., Vilchez, N., Vitale, V., Wang, P., Webb, N., Winer, B. L., Wood, K. S., Ylinen, T., and Ziegler, M.
Published: 2009
Full Text: View/download PDF

34. The Fermi Gamma-Ray Space Telescope Discovers the Pulsar in the Young Galactic Supernova Remnant CTA 1

Author: Abdo, A. A., Ackermann, M., Atwood, W. B., Baldini, L., Ballet, J., Barbiellini, G., Baring, M. G., Bastieri, D., Baughman, B. M., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Bogaert, G., Bonamente, E., Borgland, A. W., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Burnett, T. H., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Carlson, P., Casandjian, J. M., Cecchi, C., Charles, E., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Cominsky, L. R., Conrad, J., Cutini, S., Davis, D. S., Dermer, C. D., de Angelis, A., de Palma, F., Digel, S. W., Dormody, M., Silva, E. do Couto e, Drell, P. S., Dubois, R., Dumora, D., Edmonds, Y., Farnier, C., Focke, W. B., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giebels, B., Giglietto, N., Giordano, F., Glanzman, T., Godfrey, G., Grenier, I. A., Grondin, M.-H., Grove, J. E., Guillemot, L., Guiriec, S., Harding, A. K., Hartman, R. C., Hays, E., Hughes, R. E., Jóhannesson, G., Johnson, A. S., Johnson, R. P., Johnson, T. J., Johnson, W. N., Kamae, T., Kanai, Y., Kanbach, G., Katagiri, H., Kawai, N., Kerr, M., Kishishita, T., Kiziltan, B., Knödlseder, J., Kocian, M. L., Komin, N., Kuehn, F., Kuss, M., Latronico, L., Lemoine-Goumard, M., Longo, F., Lonjou, V., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Makeev, A., Marelli, M., Mazziotta, M. N., McEnery, J. E., McGlynn, S., Meurer, C., Michelson, P. F., Mineo, T., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nakamori, T., Nolan, P. L., Nuss, E., Ohno, M., Ohsugi, T., Okumura, A., Omodei, N., Orlando, E., Ormes, J. F., Ozaki, M., Paneque, D., Panetta, J. H., Parent, D., Pelassa, V., Pepe, M., Pesce-Rollins, M., Piano, G., Pieri, L., Piron, F., Porter, T. A., Rainò, S., Rando, R., Ray, P. S., Razzano, M., Reimer, A., Reimer, O., Reposeur, T., Ritz, S., Rochester, L. S., Rodriguez, A. Y., Romani, R. W., Roth, M., Ryde, F., Sadrozinski, H. F.-W., Sanchez, D., Sander, A., Parkinson, P. M. Saz, Schalk, T. L., Sellerholm, A., Sgrò, C., Siskind, E. J., Smith, D. A., Smith, P. D., Spandre, G., Spinelli, P., Starck, J.-L., Strickman, M. S., Suson, D. J., Tajima, H., Takahashi, H., Takahashi, T., Tanaka, T., Thayer, J. B., Thayer, J. G., Thompson, D. J., Thorsett, S. E., Tibaldo, L., Torres, D. F., Tosti, G., Tramacere, A., Usher, T. L., Van Etten, A., Vilchez, N., Vitale, V., Wang, P., Watters, K., Winer, B. L., Wood, K. S., Yasuda, H., Ylinen, T., and Ziegler, M.
Published: 2008
Full Text: View/download PDF

35. OSSE Observations of Active Galactic Nuclei

Author: Kurfess, J. D., Johnson, W. N., McNaron-Brown, K., Signore, M., editor, Salati, P., editor, and Vedrenne, G., editor
Published: 1995
Full Text: View/download PDF

36. Hard X-Ray and Gamma-Ray Imaging Systems Utilizing Germanium Strip Detectors

Author: Johnson, W. N., Kroeger, R. A., Kinzer, R. L., Kurfess, J. D., Inderhees, S., Phlips, B., Graham, B., Bassani, L., editor, and Di Cocco, G., editor
Published: 1995
Full Text: View/download PDF

37. Spatial and Spectral Resolution of A Germanium Strip Detector

Author: Kroeger, R. A., Johnson, W. N., Kinzer, R. L., Kurfess, J. D., Inderhees, S., Phlips, B., Gehrels, N., Bassani, L., editor, and Di Cocco, G., editor
Published: 1995
Full Text: View/download PDF

38. IGORE: Interactive GRO/OSSE Reduction Environment

Author: Grabelsky, D. A., Matz, S. M., Pendleton, J., Purcell, W. R., Ulmer, M. P., Johnson, W. N., Strickman, M. S., Zichichi, Antonino, editor, Di Gesù, V., editor, Scarsi, L., editor, Buccheri, R., editor, Crane, P., editor, Maccarone, M. C., editor, and Zimmermann, H. U., editor
Published: 1992
Full Text: View/download PDF

39. The OSSE Data Analysis System

Author: Strickman, M. S., Grove, J. E., Johnson, W. N., Kinzer, R. L., Kroeger, R. A., Kurfess, J. D., Leising, M. D., Grabelsky, D. A., Matz, S. M., Purcell, W. R., Ulmer, M. P., Cameron, R. A., Jung, G. V., Brown, K. M., Jensen, C. M., Zichichi, Antonino, editor, Di Gesù, V., editor, Scarsi, L., editor, Buccheri, R., editor, Crane, P., editor, Maccarone, M. C., editor, and Zimmermann, H. U., editor
Published: 1992
Full Text: View/download PDF

40. NOVAE: Fermi establishes classical novae as a distinct class of gamma-ray sources

Author: Ackermann, M., Ajello, M., Albert, A., Baldini, L, Ballet, J., Barbiellini, G., Bastieri, D., Bellazzini, R., Bissaldi, E., Blandford, R. D., Bloom, E. D., Bottacini, E., Brandt, T. J., Bregeon, J., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caragiulo, M., Caraveo, P. A., Cavazzuti, E., Charles, E., Chekhtman, A., Cheung, C. C., Chiang, J., Chiaro, G., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Corbel, S., DʼAmmando, F., Angelis, A. de, Hartog, P. R. den, Palma, F. de, Dermer, C. D., Desiante, R., Digel, S. W., Di Venere, L., do Couto e Silva, E., Donato, D., Drell, P. S., Drlica-Wagner, A., Favuzzi, C., Ferrara, E. C., Focke, W. B., Franckowiak, A., Fuhrmann, L, Fukazawa, Y., Fusco, P., Gargano, F., Gasparrini, D., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Grove, J. E., Guiriec, S., Hadasch, D., Harding, A. K., Hayashida, M., Hays, E., Hewitt, J. W., Hill, A. B., Hou, X., Jean, P., Jogler, T., Jóhannesson, G., Johnson, A. S., Johnson, W. N., Kerr, M., Knödlseder, J., Kuss, M., Larsson, S., Latronico, L., Lemoine-Goumard, M., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Manfreda, A., Martin, P., Massaro, F., Mayer, M., Mazziotta, M. N., McEnery, J. E., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Monzani, M. 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., Panetta, J. H., Perkins, J. S., Pesce-Rollins, M., Piron, F., Pivato, G., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Reposeur, T., Parkinson, P. M. Saz, Schaal, M., Schulz, A., Sgrò, C., Siskind, E. J., Spandre, G., Spinelli, P., Stawarz, Ł, Suson, D. J., Takahashi, H., Tanaka, T., Thayer, J. G., Thayer, J. B., Thompson, D. J., Tibaldo, L., Tinivella, M., Torres, D. F., Tosti, G., Troja, E., Uchiyama, Y., Vianello, G., Winer, B. L., Wolff, M. T., Wood, D. L., Wood, K. S., Wood, M., Charbonnel, S., Corbet, R. H. D., De Gennaro Aquino, I., Edlin, J. P., Mason, E., Schwarz, G. J., Shore, S. N., Starrfield, S., and Teyssier, F.
Published: 2014
Full Text: View/download PDF

41. Gamma-Ray Emission Concurrent with the Nova in the Symbiotic Binary V407 Cygni

Author: Abdo, A. A., Ackermann, M., Ajello, M., Atwood, W. B., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bouvier, A., Brandt, T. J., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Buehler, R., Burnett, T. H., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Carrigan, S., Casandjian, J. M., Cecchi, C., Celik, O., Charles, E., Chaty, S., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Corbel, S., Corbet, R., DeCesar, M. E., den Hartog, P. R., Dermer, C. D., de Palma, F., Digel, S. W., Donato, D., do Couto e Silva, E., Drell, P. S., Dubois, R., Dubus, G., Dumora, D., Favuzzi, C., Fegan, S. J., Ferrara, E. C, Fortin, P., Frailis, M., Fuhrmann, L., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gaspamini, D., Gehrels, N., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Grondin, M.-H., Grove, J. E., Guiriec, S., Hadasch, D., Harding, A. K., Hayashida, M., Hays, E., Healey, S. E., Hill, A. B., Horan, D., Hughes, R. E., Itoh, R., Jean, P., Jóhannesson, G., Johnson, A. S., Johnson, R. P., Johnson, T. J., Johnson, W. N., Kamae, T., Katagiri, H., Kataoka, J., Kerr, M., Knödlseder, J., Koerding, E., Kuss, M., Lande, J., Latronico, L., Lee, S.-H., Lemoine-Goumard, M., Garde, Llena M., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Makeev, A., Mazziotta, M. N., McConville, W., McEnery, J. E., Mehault, J., Michelson, P. F., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nakamori, T., Naumann-Godo, M., Nestoras, I., Nolan, P. L., Norris, J. P., Nuss, E., Ohno, M., Ohsugi, T., Okumura, A., Omodei, N., Orlando, E., Ormes, J. F., Ozaki, M., Paneque, D., Panetta, J. H., Parent, D., Pelassa, V., Pepe, M., Pesce-Rollins, M., Piron, F., Porter, T. A, Raino, S., Rando, R., Ray, P. S., Razzano, M., Razzaque, S., Rea, N., Reimer, A., Reimer, O., Reposeur, T., Ripken, J., Ritz, S., Romani, R. W., Roth, M., Sadrozinski, H. F.-W., Sander, A., Saz Parkinson, P. M., Scargle, J. D., Schinzel, F. K., Sgrò, C., Shaw, M. S., Siskind, E. J., Smith, D. A., Smith, P. D., Sokolovsky, K. V., Spandre, G., Spinelli, P., Stawarz, L., Strickman, M. S., Suson, D. J., Takahashi, H., Takahashi, T., Tanaka, T., Tanaka, Y., Thayer, J. B., Thayer, J. G., Thompson, D. J., Tibaldo, L., Torres, D. F., Tosti, G., Tramacere, A., Uchiyama, Y., Usher, T. L, Vandenbroucke, J., Vasileiou, V., Vilchez, N., Vitale, V., Waite, A. P., Wallace, E., Wang, P., Winer, B. L, Wolff, M. T., Wood, K. S., Yang, Z., Ylinen, T., Ziegler, M., Maehara, H., Nishiyama, K., Kabashima, F., Bach, U., Bower, G. C., Falcone, A., Forster, J. R., Henden, A., Kawabata, K. S., Koubsky, P., Mukai, K., Nelson, T., Oates, S. R., Sakimoto, K., Sasada, M., Shenavrin, V. I., Shore, S. N., Skinner, G. K., Sokoloski, J., Stroh, M., Tatarnikov, A. M., Uemura, M., Wahlgren, G. M., and Yamanaka, M.
Published: 2010
Full Text: View/download PDF

42. Fermi Gamma-Ray Imaging of a Radio Galaxy

Author: Abdo, A. A., Ackermann, M., Ajello, M., Atwood, W. B., Baldini, L, Ballet, J., Barbiellini, G., Bastieri, D., Baughman, B. M., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Burnett, T. H., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cavazzuti, E., Cecchi, C., Çelik, Ö., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Colafrancesco, S., Cominsky, L. R., Conrad, J., Costamante, L, Cutini, S., Davis, D. S., Dermer, C. D., de Angelis, A., de Palma, F., Digel, S. W., do Couto e Silva, E., Drell, P. S., Dubois, R., Dumora, D., Famier, C., Favuzzi, C., Fegan, S. J., Finke, J., Focke, W. B., Fortin, P., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Georganopoulos, M., Germani, S., Giebels, B., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Grove, J. E., Guillemot, L, Guiriec, S., Hanabata, Y., Harding, A. K., Hayashida, M., Hays, E., Hughes, R. E., Jackson, M. S., Johannesson, G., Johnson, A. S., Johnson, T. J., Johnson, W. N., Kamae, T., Katagiri, H., Kataoka, J., Kawai, N., Kerr, M., Knödlseder, J., Kocian, M. L., Kuss, M., Lande, J., Latronico, L., Lemoine-Goumard, M., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Makeev, A., Mazziotta, M. N., McConville, W., McEnery, J. E., Meurer, C., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nolan, P. L., Norris, J. P., Nuss, E., Ohsugi, T., Omodei, N., Orlando, E., Ormes, J. F., Paneque, D., Parent, D., Pelassa, V., Pepe, M., Pesce-Rollins, M., Piron, F., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Reposeur, T., Ritz, S., Rochester, L. S., Rodriguez, A. Y., Romani, R. W., Roth, M., Ryde, F., Sadrozinski, H. F.-W., Sambruna, R., Sanchez, D., Sander, A., Saz Parkinson, P. M., Scargle, J. D., Sgrò, C., Siskind, E. J., Smith, D. A., Smith, P. D., Spandre, G., Spinelli, P., Starck, J.-L., Stawarz, Ł., Strickman, M. S., Suson, D. J., Tajima, H., Takahashi, H., Takahashi, T., Tanaka, T., Thayer, J. B., Thayer, J. G., Thompson, D. J., Tibaldo, L., Torres, D. F., Tosti, G., Tramacere, A., Uchiyama, Y., Usher, T. L., Vasileiou, V., Vilchez, N., Vitale, V., Waite, A. P., Wallace, E., Wang, P., Winer, B. L., Wood, K. S., Ylinen, T., Ziegler, M., Hardcastle, M. J., and Kazanas, D.
Published: 2010
Full Text: View/download PDF

43. A change in the optical polarization associated with a γ-ray flare in the blazar 3C 279

Author: Abdo, A. A., Ackermann, M., Ajello, M., Axelsson, M., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Baughman, B. M., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Bock, D. C.-J., Bogart, J. R., Bonamente, E., Borgland, A. W., Bouvier, A., Bregeon, J., Brez, A., Brigida, M., Bruel, P., Burnett, T. H., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cavazzuti, E., Cecchi, C., Çelik, Ö., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Collmar, W., Cominsky, L. R., Conrad, J., Corbel, S., Corbet, R., Costamante, L., Cutini, S., Dermer, C. D., de Angelis, A., de Palma, F., Digel, S. W., do Couto e Silva, E., Drell, P. S., Dubois, R., Dumora, D., Farnier, C., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Focke, W. B., Fortin, P., Frailis, M., Fuhrmann, L., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giebels, B., Giglietto, N., Giommi, P., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Grove, J. E., Guillemot, L., Guiriec, S., Hanabata, Y., Harding, A. K., Hayashida, M., Hays, E., Horan, D., Hughes, R. E., Iafrate, G., Itoh, R., Jackson, M. S., Jóhannesson, G., Johnson, A. S., Johnson, W. N., Kadler, M., Kamae, T., Katagiri, H., Kataoka, J., Kawai, N., Kerr, M., Knödlseder, J., Kocian, M. L., Kuss, M., Lande, J., Larsson, S., Latronico, L., Lemoine-Goumard, M., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Macquart, J., Madejski, G. M., Makeev, A., Max-Moerbeck, W., Mazziotta, M. N., McConville, W., McEnery, J. E., McGlynn, S., Meurer, C., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nestoras, I., Nolan, P. L., Norris, J. P., Nuss, E., Ohsugi, T., Okumura, A., Omodei, N., Orlando, E., Ormes, J. F., Paneque, D., Panetta, J. H., Parent, D., Pavlidou, V., Pearson, T. J., Pelassa, V., Pepe, M., Pesce-Rollins, M., Piron, F., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Readhead, A., Reimer, A., Reimer, O., Reposeur, T., Reyes, L. C., Richards, J. L., Rochester, L. S., Rodriguez, A. Y., Roth, M., Ryde, F., Sadrozinski, H. F.-W., Sanchez, D., Sander, A., Saz Parkinson, P. M., Scargle, J. D., Sgrò, C., Shaw, M. S., Shrader, C., Siskind, E. J., Smith, D. A., Smith, P. D., Spandre, G., Spinelli, P., Stawarz, L., Stevenson, M., Strickman, M. S., Suson, D. J., Tajima, H., Takahashi, H., Takahashi, T., Tanaka, T., Taylor, G. B., Thayer, J. B., Thayer, J. G., Thompson, D. J., Tibaldo, L., Torres, D. F., Tosti, G., Tramacere, A., Uchiyama, Y., Usher, T. L., Vasileiou, V., Vilchez, N., Vitale, V., Waite, A. P., Wang, P., Wehrle, A. E., Winer, B. L., Wood, K. S., Ylinen, T., Zensus, J. A., Ziegler, M., Uemura, M., Ikejiri, Y., Kawabata, K. S., Kino, M., Sakimoto, K., Sasada, M., Sato, S., Yamanaka, M., Villata, M., Raiteri, C. M., Agudo, I., Aller, H. D., Aller, M. F., Angelakis, E., Arkharov, A. A., Bach, U., Benítez, E., Berdyugin, A., Blinov, D. A., Boettcher, M., Buemi, C. S., Chen, W. P., Dolci, M., Dultzin, D., Efimova, N. V., Gurwell, M. A., Gusbar, C., Gómez, J. L., Heidt, J., Hiriart, D., Hovatta, T., Jorstad, S. G., Konstantinova, T. S., Kopatskaya, E. N., Koptelova, E., Kurtanidze, O. M., Lahteenmaki, A., Larionov, V. M., Larionova, E. G., Leto, P., Lin, H. C., Lindfors, E., Marscher, A. P., McHardy, I. M., Melnichuk, D. A., Mommert, M., Nilsson, K., Di Paola, A., Reinthal, R., Richter, G. M., Roca-Sogorb, M., Roustazadeh, P., Sigua, L. A., Takalo, L. O., Tornikoski, M., Trigilio, C., Troitsky, I. S., Umana, G., Villforth, C., Grainge, K., Moderski, R., Nalewajko, K., and Sikora, M.
Published: 2010
Full Text: View/download PDF

44. Modulated High-Energy Gamma-Ray Emission from the Microquasar Cygnus X-3

Author: Abdo, A. A., Ackermann, M., Ajello, M., Axelsson, M., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Baughman, B. M., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Brez, A., Brigida, M., Bruel, P., Burnett, T. H., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Çelik, Ö., Chaty, S., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Cominsky, L R., Conrad, J., Corbel, S., Corbet, R., Dermer, C. D., de Palma, F., Digel, S. W., do Couto e Silva, E., Drell, P. S., Dubois, R., Dubus, G., Dumora, D., Farnier, C., Favuzzi, C., Fegan, S. J., Focke, W. B., Fortin, P., Frailis, M., Fusco, P., Gargano, F., Gehrels, N., Germani, S., Giavitto, G., Giebels, B., Giglietto, N., Giordano, F., Glanzman, T., Godfrey, G., Grenier, I. A., Grondin, M.-H., Grove, J. E., Guillemot, L, Guiriec, S., Hanabata, Y., Harding, A. K., Hayashida, M., Hays, E., Hill, A. B., Hjalmarsdotter, L., Horan, D., Hughes, R. E., Jackson, M. S., Jóhannesson, G., Johnson, A. S., Johnson, T. J., Johnson, W. N., Kamae, T., Katagiri, H., Kawai, N., Kerr, M., Knödlseder, J., Kocian, M. L., Koerding, E., Kuss, M., Lande, J., Latronico, L., Lemoine-Goumard, M., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Makeev, A., Marchand, L., Marelli, M., Max-Moerbeck, W., Mazziotta, M. N., McColl, N., McEnery, J. E., Meurer, C., Michelson, P. F., Migliari, S., Mitthumsiri, W., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nolan, P. L, Norris, J. P., Nuss, E., Ohsugi, T., Omodei, N., Ong, R. A., Ormes, J. F., Paneque, D., Parent, D., Pelassa, V., Pepe, M., Pesce-Rollins, M., Piron, F., Pooley, G., Porter, T. A., Pottschmidt, K., Rainò, S., Rando, R., Ray, P. S., Razzano, M., Rea, N., Readhead, A., Reimer, A., Reimer, O., Richards, J. L., Rochester, L S., Rodriguez, J., Rodriguez, A. Y., Romani, R. W., Ryde, F., Sadrozinski, H. F.-W., Sander, A., Saz Parkinson, P. M., Sgrò, C., Siskind, E. J., Smith, D. A., Smith, P. D., Spinelli, P., Starck, J.-L, Stevenson, M., Strickman, M. S., Suson, D. J., Takahashi, H., Tanaka, T., Thayer, J. B., Thompson, D. J., Tibaldo, L, Tomsick, J. A., Torres, D. F., Tosti, G., Tramacere, A., Uchiyama, Y., Usher, T. L, Vasileiou, V., Vilchez, N., Vitale, V., Waite, A. P., Wang, P., Wilms, J., Winer, B. L., Wood, K. S., Ylinen, T., and Ziegler, M.
Published: 2009
Full Text: View/download PDF

45. A limit on the variation of the speed of light arising from quantum gravity effects

Author: Abdo, A. A., Ackermann, M., Ajello, M., Asano, K., Atwood, W. B., Axelsson, M., Baldini, L., Ballet, J., Barbiellini, G., Baring, M. G., Bastieri, D., Bechtol, K., Bellazzini, R., Berenji, B., Bhat, P. N., Bissaldi, E., Bloom, E. D., Bonamente, E., Bonnell, J., Borgland, A. W., Bouvier, A., Bregeon, J., Brez, A., Briggs, M. S., Brigida, M., Bruel, P., Burgess, J. M., Burnett, T. H., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Çelik, Ö., Chaplin, V., Charles, E., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Cominsky, L. R., Connaughton, V., Conrad, J., Cutini, S., Dermer, C. D., de Angelis, A., de Palma, F., Digel, S. W., Dingus, B. L., do Couto e Silva, E., Drell, P. S., Dubois, R., Dumora, D., Farnier, C., Favuzzi, C., Fegan, S. J., Finke, J., Fishman, G., Focke, W. B., Foschini, L., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Gibby, L., Giebels, B., Giglietto, N., Giordano, F., Glanzman, T., Godfrey, G., Granot, J., Greiner, J., Grenier, I. A., Grondin, M.-H., Grove, J. E., Grupe, D., Guillemot, L., Guiriec, S., Hanabata, Y., Harding, A. K., Hayashida, M., Hays, E., Hoversten, E. A., Hughes, R. E., Jóhannesson, G., Johnson, A. S., Johnson, R. P., Johnson, W. N., Kamae, T., Katagiri, H., Kataoka, J., Kawai, N., Kerr, M., Kippen, R. M., Knödlseder, J., Kocevski, D., Kouveliotou, C., Kuehn, F., Kuss, M., Lande, J., Latronico, L., Lemoine-Goumard, M., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Makeev, A., Mazziotta, M. N., McBreen, S., McEnery, J. E., McGlynn, S., Mészáros, P., Meurer, C., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Moretti, E., Morselli, A., Moskalenko, I. V., Murgia, S., Nakamori, T., Nolan, P. L., Norris, J. P., Nuss, E., Ohno, M., Ohsugi, T., Omodei, N., Orlando, E., Ormes, J. F., Ozaki, M., Paciesas, W. S., Paneque, D., Panetta, J. H., Parent, D., Pelassa, V., Pepe, M., Pesce-Rollins, M., Petrosian, V., Piron, F., Porter, T. A., Preece, R., Rainò, S., Ramirez-Ruiz, E., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Reposeur, T., Ritz, S., Rochester, L. S., Rodriguez, A. Y., Roth, M., Ryde, F., Sadrozinski, H. F.-W., Sanchez, D., Sander, A., Saz Parkinson, P. M., Scargle, J. D., Schalk, T. L., Sgrò, C., Siskind, E. J., Smith, D. A., Smith, P. D., Spandre, G., Spinelli, P., Stamatikos, M., Stecker, F. W., Strickman, M. S., Suson, D. J., Tajima, H., Takahashi, H., Takahashi, T., Tanaka, T., Thayer, J. B., Thayer, J. G., Thompson, D. J., Tibaldo, L., Toma, K., Torres, D. F., Tosti, G., Troja, E., Uchiyama, Y., Uehara, T., Usher, T. L., van der Horst, A. J., Vasileiou, V., Vilchez, N., Vitale, V., von Kienlin, A., Waite, A. P., Wang, P., Wilson-Hodge, C., Winer, B. L., Wood, K. S., Wu, X. F., Yamazaki, R., Ylinen, T., and Ziegler, M.
Published: 2009
Full Text: View/download PDF

46. Fermi Observations of High-Energy Gamma-Ray Emission from GRB 080916C

Author: Abdo, A. A., Ackermann, M., Arimoto, M., Asano, K., Atwood, W. B., Axelsson, M., Baldini, L., Ballet, J., Band, D. L., Barbiellini, G., Baring, M. G., Bastieri, D., Battelino, M., Baughman, B. M., Bechtol, K., Bellardi, F., Bellazzini, R., Berenji, B., Bhat, P. N., Bissaldi, E., Blandford, R. D., Bloom, E. D., Bogaert, G., Bogart, J. R., Bonamente, E., Bonnell, J., Borgland, A. W., Bouvier, A., Bregeon, J., Brez, A., Briggs, M. S., Brigida, M., Bruel, P., Burnett, T. H., Burrows, D., Busetto, G., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Ceccanti, M., Cecchi, C., Celotti, A., Charles, E., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Cominsky, L. R., Connaughton, V., Conrad, J., Costamante, L., Cutini, S., DeKlotz, M., Dermer, C. D., de Angelis, A., de Palma, F., Digel, S. W., Dingus, B. L., do Couto e Silva, E., Drell, P. S., Dubois, R., Dumora, D., Edmonds, Y., Evans, P. A., Fabiani, D., Farnier, C., Favuzzi, C., Finke, J., Fishman, G., Focke, W. B., Frailis, M., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giebels, B., Giglietto, N., Giommi, P., Giordano, F., Glanzman, T., Godfrey, G., Goldstein, A., Granot, J., Greiner, J., Grenier, I. A., Grondin, M.-H., Grove, J. E., Guillemot, L., Guiriec, S., Haller, G., Hanabata, Y., Harding, A. K., Hayashida, M., Hays, E., Morata, Hernando J. A., Hoover, A., Hughes, R. E., Jóhannesson, G., Johnson, A. S., Johnson, R. P., Johnson, T. J., Johnson, W. N., Kamae, T., Katagiri, H., Kataoka, J., Kavelaars, A., Kawai, N., Kelly, H., Kennea, J., Kerr, M., Kippen, R. M., Knödlseder, J., Kocevski, D., Kocian, M. L., Komin, N., Kouveliotou, C., Kuehn, F., Kuss, M., Lande, J., Landriu, D., Larsson, S., Latronico, L., Lavalley, C., Lee, B., Lee, S.-H., Lemoine-Goumard, M., Lichti, G. G., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Makeev, A., Marangelli, B., Mazziotta, M. N., McBreen, S., McEnery, J. E., McGlynn, S., Meegan, C., Mészáros, P., Meurer, C., Michelson, P. F., Minuti, M., Mirizzi, N., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Moretti, E., Morselli, A., Moskalenko, I. V., Murgia, S., Nakamori, T., Nelson, D., Nolan, P. L., Norris, J. P., Nuss, E., Ohno, M., Ohsugi, T., Okumura, A., Omodei, N., Orlando, E., Ormes, J. F., Ozaki, M., Paciesas, W. S., Paneque, D., Panetta, J. H., Parent, D., Pelassa, V., Pepe, M., Perri, M., Pesce-Rollins, M., Petrosian, V., Pinchera, M., Piron, F., Porter, T. A., Preece, R., Rainò, S., Ramirez-Ruiz, E., Rando, R., Rapposelli, E., Razzano, M., Razzaque, S., Rea, N., Reimer, A., Reimer, O., Reposeur, T., Reyes, L. C., Ritz, S., Rochester, L. S., Rodriguez, A. Y., Roth, M., Ryde, F., Sadrozinski, H. F.-W., Sanchez, D., Sander, A., Parkinson, Saz P. M., Scargle, J. D., Schalk, T. L., Segal, K. N., Sgrò, C., Shimokawabe, T., Siskind, E. J., Smith, D. A., Smith, P. D., Spandre, G., Spinelli, P., Stamatikos, M., Starck, J.-L, Stecker, F. W., Steinle, H., Stephens, T. E., Strickman, M. S., Suson, D. J., Tagliaferri, G., Tajima, H., Takahashi, H., Takahashi, T., Tanaka, T., Tenze, A., Thayer, J. B., Thayer, J. G., Thompson, D. J., Tibaldo, L., Torres, D. F., Tosti, G., Tramacere, A., Turri, M., Tuvi, S., Usher, T. L., van der Horst, A. J., Vigiani, L., Vilchez, N., Vitale, V., von Kienlin, A., Waite, A. P., Williams, D. A., Wilson-Hodge, C., Winer, B. L., Wood, K. S., Wu, X. F., Yamazaki, R., Ylinen, T., and Ziegler, M.
Published: 2009

47. NRL SSD Research Achievements: 19701980. Volume 2

Author: Dahlburg, Jill, primary, Doschek, George, primary, Budzien, Scott, primary, Howard, Russell, primary, Englert, Christoph, primary, Johnson, W. N., primary, Socker, Dennis, primary, and Wood, Kent, primary
Published: 2015
Full Text: View/download PDF

48. NRL SSD Research Achievements: 19601970. Volume 1

Author: Dahlburg, Jill, primary, Doschek, George, primary, Englert, Christoph, primary, Howard, Russell, primary, Johnson, W. N., primary, Kowalski, Michael, primary, Socker, Dennis, primary, and Wood, Kent, primary
Published: 2015
Full Text: View/download PDF

49. BATSE/OSSE rapid burst response

Author: Matz, S. M., Grove, J. E., Johnson, W. N., Kurfess, J. D., Share, G. H., Fishman, G. J., and Meegan, C. A.
Published: 1995
Full Text: View/download PDF

50. Osse limits on pre- and post-burst emission

Author: Matz, S. M., Grove, J. E., Johnson, W. N., Kurfess, J. D., and Share, G. H.
Published: 1995
Full Text: View/download PDF

Catalog

Books, media, physical & digital resources

See catalog results

Searchworks

Select search scope, currently: Articles Catalog books, media & more in Jio Institute collections Articles journal articles & other e-resources

Search

Search Constraints

Refine your results

Search Limiters

Topic

Publication Year Range

Language

Publication Type

Journal

Database

Publisher

902 results on '"Johnson, W. N."'

Search Results

Catalog

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources