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1,694 results on '"Gustafsson, M."'

1. GRB 221009A: the B.O.A.T Burst that Shines in Gamma Rays

Author: Axelsson, M., Ajello, M., Arimoto, M., Baldini, L., Ballet, J., Baring, M. G., Bartolini, C., Bastieri, D., Gonzalez, J. Becerra, Bellazzini, R., Berenji, B., Bissaldi, E., Blandford, R. D., Bonino, R., Bruel, P., Buson, S., Cameron, R. A., Caputo, R., Caraveo, P. A., Cavazzuti, E., Cheung, C. C., Chiaro, G., Cibrario, N., Ciprini, S., Cozzolongo, G., Orestano, P. Cristarella, Crnogorcevic, M., Cuoco, A., Cutini, S., D'Ammando, F., De Gaetano, S., Di Lalla, N., Dinesh, A., Di Tria, R., Di Venere, L., Domínguez, A., Fegan, S. J., Ferrara, E. C., Fiori, A., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Galanti, G., Gargano, F., Gasbarra, C., Germani, S., Giacchino, F., Giglietto, N., Giliberti, M., Gill, R., Giordano, F., Giroletti, M., Granot, J., Green, D., Grenier, I. A., Guiriec, S., Gustafsson, M., Hashizume, M., Hays, E., Hewitt, J. W., Horan, D., Kayanoki, T., Kuss, M., Laviron, A., Li, J., Liodakis, I., Longo, F., Loparco, F., Lorusso, L., Lott, B., Lovellette, M. N., Lubrano, P., Maldera, S., Malyshev, D., Manfreda, A., Martí-Devesa, G., Martinelli, R., Castellanos, I. Martinez, Mazziotta, M. N., McEnery, J. E., Mereu, I., Meyer, M., Michelson, P. F., Mirabal, N., Mitthumsiri, W., Mizuno, T., Monti-Guarnieri, P., Monzani, M. E., Morishita, T., Morselli, A., Moskalenko, I. V., Negro, M., Niwa, R., Omodei, N., Orienti, M., Orlando, E., Paneque, D., Panzarini, G., Persic, M., Pesce-Rollins, M., Petrosian, V., Pillera, R., Piron, F., Porter, T. A., Principe, G., Racusin, J. L., Rainò, S., Rando, R., Rani, B., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Ryde, F., Sánchez-Conde, M., Parkinson, P. M. Saz, Serini, D., Sgrò, C., Sharma, V., Siskind, E. J., Spandre, G., Spinelli, P., Suson, D. J., Tajima, H., Tak, D., Thayer, J. B., Torres, D. F., Valverde, J., Zaharijas, G., Lesage, S., Briggs, M. S., Burns, E., Bala, S., Bhat, P. N., Cleveland, W. H., Dalessi, S., de Barra, C., Gibby, M., Giles, M. M., Hamburg, R., Hristov, B. A., Hui, C. M., Kocevski, D., Mailyan, B., Malacaria, C., McBreen, S., Poolakkil, S., Roberts, O. J., Scotton, L., Veres, P., von Kienlin, A., Wilson-Hodge, C. A., and Wood, J.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We present a complete analysis of Fermi Large Area Telescope (LAT) data of GRB 221009A, the brightest Gamma-Ray Burst (GRB) ever detected. The burst emission above 30 MeV detected by the LAT preceded by 1 s the low-energy (< 10 MeV) pulse that triggered the Fermi Gamma-Ray Burst Monitor (GBM), as has been observed in other GRBs. The prompt phase of GRB 221009A lasted a few hundred seconds. It was so bright that we identify a Bad Time Interval (BTI) of 64 seconds caused by the extremely high flux of hard X-rays and soft gamma rays, during which the event reconstruction efficiency was poor and the dead time fraction quite high. The late-time emission decayed as a power law, but the extrapolation of the late-time emission during the first 450 seconds suggests that the afterglow started during the prompt emission. We also found that high-energy events observed by the LAT are incompatible with synchrotron origin, and, during the prompt emission, are more likely related to an extra component identified as synchrotron self-Compton (SSC). A remarkable 400 GeV photon, detected by the LAT 33 ks after the GBM trigger and directionally consistent with the location of GRB 221009A, is hard to explain as a product of SSC or TeV electromagnetic cascades, and the process responsible for its origin is uncertain. Because of its proximity and energetic nature, GRB 221009A is an extremely rare event., Comment: 60 pages, 38 figures, 9 tables
Published: 2024

2. Fermi-GBM Discovery of GRB 221009A: An Extraordinarily Bright GRB from Onset to Afterglow

Author: Lesage, S., Veres, P., Briggs, M. S., Goldstein, A., Kocevski, D., Burns, E., Wilson-Hodge, C. A., Bhat, P. N., Huppenkothen, D., Fryer, C. L., Hamburg, R., Racusin, J., Bissaldi, E., Cleveland, W. H., Dalessi, S., Fletcher, C., Giles, M. M., Hristov, B. A., Hui, C. M., Mailyan, B., Malacaria, C., Poolakkil, S., Roberts, O. J., von Kienlin, A., Wood, J., Ajello, M., Arimoto, M., Baldini, L., Ballet, J., Baring, M. G., Bastieri, D., Gonzalez, J. Becerra, Bellazzini, R., Blandford, R. D., Bonino, R., Bruel, P., Buson, S., Cameron, R. A., Caputo, R., Caraveo, P. A., Cavazzuti, E., Chiaro, G., Cibrario, N., Ciprini, S., Orestano, P. Cristarella, Crnogorcevic, M., Cuoco, A., Cutini, S., DAmmando, F., De Gaetano, S., Di Lalla, N., Di Venere, L., Dominguez, A., Fegan, S. J., Ferrara, E. C., Fleischhack, H., Fukazawa, Y., Funk, S., Fusco, P., Galanti, G., Gammaldi, V., Gargano, F., Gasbarra, C., Gasparrini, D., Germani, S., Giacchino, F., Giglietto, N., Gill, R., Giroletti, M., Granot, J., Green, D., Grenier, I. A., Guiriec, S., Gustafsson, M., Hays, E., Hewitt, J. W., Horan, D., Hou, X., Kuss, M., Latronico, L., Laviron, A., Lemoine-Goumard, M., Li, J., Liodakis, I., Longo, F., Loparco, F., Lorusso, L., Lovellette, M. N., Lubrano, P., Maldera, S., Manfreda, A., Marti-Devesa, G., Mazziotta, M. N., McEnery, J. E., Mereu, I., Meyer, M., Michelson, P. F., Mizuno, T., Monzani, M. E., Morselli, A., Moskalenko, I. V., Negro, M., Nuss, E., Omodei, N., Orlando, E., Ormes, J. F., Paneque, D., Panzarini, G., Persic, M., Pesce-Rollins, M., Pillera, R., Piron, F., Poon, H., Porter, T. A., Principe, G., Raino, S., Rando, R., Rani, B., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Ryde, F., Sanchez-Conde, M., Parkinson, P. M. Saz, Scotton, L., Serini, D., Sgro, C., Sharma, V., Siskind, E. J., Spandre, G., Spinelli, P., Tajima, H., Torres, D. F., Valverde, J., Venters, T., Wadiasingh, Z., Wood, K., and Zaharijas, G.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We report the discovery of GRB 221009A, the highest flux gamma-ray burst ever observed by the Fermi Gamma-ray Burst Monitor (GBM). This GRB has continuous prompt emission lasting more than 600 seconds which smoothly transitions to afterglow visible in the GBM energy range (8 keV--40 MeV), and total energetics higher than any other burst in the GBM sample. By using a variety of new and existing analysis techniques we probe the spectral and temporal evolution of GRB 221009A. We find no emission prior to the GBM trigger time (t0; 2022 October 9 at 13:16:59.99 UTC), indicating that this is the time of prompt emission onset. The triggering pulse exhibits distinct spectral and temporal properties suggestive of the thermal, photospheric emission of shock-breakout, with significant emission up to $\sim$15 MeV. We characterize the onset of external shock at t0+600 s and find evidence of a plateau region in the early-afterglow phase which transitions to a slope consistent with Swift-XRT afterglow measurements. We place the total energetics of GRB 221009A in context with the rest of the GBM sample and find that this GRB has the highest total isotropic-equivalent energy ($\textrm{E}_{\gamma,\textrm{iso}}=1.0\times10^{55}$ erg) and second highest isotropic-equivalent luminosity ($\textrm{L}_{\gamma,\textrm{iso}}=9.9\times10^{53}$ erg/s) based on redshift of z = 0.151. These extreme energetics are what allowed us to observe the continuously emitting central engine of GBM from the beginning of the prompt emission phase through the onset of early afterglow., Comment: 26 pages 7 figures - accepted for publication in ApJL
Published: 2023
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3. Search for neutrino lines from dark matter annihilation and decay with IceCube

Author: The IceCube Collaboration, Abbasi, R., Ackermann, M., Adams, J., Agarwalla, S. K., Aguilar, J. A., Ahlers, M., Alameddine, J. M., Amin, N. M., Andeen, K., Anton, G., Argüelles, C., Ashida, Y., Athanasiadou, S., Axani, S. N., Bai, X., V., A. Balagopal, Baricevic, M., Barwick, S. W., Basu, V., Bay, R., Beatty, J. J., Becker, K. -H., Tjus, J. Becker, Beise, J., Bellenghi, C., BenZvi, S., Berley, D., Bernardini, E., Besson, D. Z., Binder, G., Bindig, D., Blaufuss, E., Blot, S., Bontempo, F., Book, J. Y., Meneguolo, C. Boscolo, Böser, S., Botner, O., Böttcher, J., Bourbeau, E., Braun, J., Brinson, B., Brostean-Kaiser, J., Burley, R. T., Busse, R. S., Butterfield, D., Campana, M. A., Carloni, K., Carnie-Bronca, E. G., Chattopadhyay, S., Chen, C., Chen, Z., Chirkin, D., Choi, S., Clark, B. A., Classen, L., Coleman, A., Collin, G. H., Connolly, A., Conrad, J. M., Coppin, P., Correa, P., Countryman, S., Cowen, D. F., Dave, P., De Clercq, C., DeLaunay, J. J., López, D. Delgado, Dembinski, H., Deng, S., Deoskar, K., Desai, A., Desiati, P., de Vries, K. D., de Wasseige, G., DeYoung, T., Diaz, A., Díaz-Vélez, J. C., Dittmer, M., Domi, A., Dujmovic, H., DuVernois, M. A., Ehrhardt, T., Aisati, C. El, Eller, P., Engel, R., Erpenbeck, H., Evans, J., Evenson, P. A., Fan, K. L., Fang, K., Fazely, A. R., Fedynitch, A., Feigl, N., Fiedlschuster, S., Finley, C., Fischer, L., Fox, D., Franckowiak, A., Friedman, E., Fritz, A., Fürst, P., Gaisser, T. K., Gallagher, J., Ganster, E., Garcia, A., Garrappa, S., Gerhardt, L., Ghadimi, A., Glaser, C., Glauch, T., Glüsenkamp, T., Gustafsson, M., Goehlke, N., Gonzalez, J. G., Goswami, S., Grant, D., Gray, S. J., Griffin, S., Griswold, S., Günther, C., Gutjahr, P., Haack, C., Hallgren, A., Halliday, R., Halve, L., Halzen, F., Hambye, T., Hamdaoui, H., Minh, M. Ha, Hanson, K., Hardin, J., Harnisch, A. A., Hatch, P., Haungs, A., Hauser, S., Helbing, K., Hellrung, J., Henningsen, F., Heuermann, L., Hickford, S., Hidvegi, A., Hill, C., Hill, G. C., Hoffman, K. D., Hoshina, K., Hou, W., Huber, T., Hultqvist, K., Hünnefeld, M., Hussain, R., Hymon, K., In, S., Iovine, N., Ishihara, A., Jacquart, M., Jansson, M., Japaridze, G. S., Jayakumar, K., Jeong, M., Jin, M., Jones, B. J. P., Kang, D., Kang, W., Kang, X., Kappes, A., Kappesser, D., Kardum, L., Karg, T., Karl, M., Karle, A., Katz, U., Kauer, M., Kelley, J. L., Zathul, A. Khatee, Kheirandish, A., Kin, K., Kiryluk, J., Klein, S. R., Kochocki, A., Koirala, R., Kolanoski, H., Kontrimas, T., Köpke, L., Kopper, C., Koskinen, D. J., Koundal, P., Kovacevich, M., Kowalski, M., Kozynets, T., Kruiswijk, K., Krupczak, E., Kumar, A., Kun, E., Kurahashi, N., Lad, N., Gualda, C. Lagunas, Lamoureux, M., Larson, M. J., Lauber, F., Lazar, J. P., Lee, J. W., DeHolton, K. Leonard, Leszczyńska, A., Lincetto, M., Liu, Q. R., Liubarska, M., Lohfink, E., Love, C., Mariscal, C. J. Lozano, Lu, L., Lucarelli, F., Ludwig, A., Luszczak, W., Lyu, Y., Ma, W. Y., Madsen, J., Mahn, K. B. M., Makino, Y., Mancina, S., Sainte, W. Marie, Mari{ş}, I. C., Marka, S., Marka, Z., Marsee, M., Martinez-Soler, I., Maruyama, R., Mayhew, F., McElroy, T., McNally, F., Mead, J. V., Meagher, K., Mechbal, S., Medina, A., Meier, M., Meighen-Berger, S., Merckx, Y., Merten, L., Micallef, J., Mockler, D., Montaruli, T., Moore, R. W., Morii, Y., Morse, R., Moulai, M., Mukherjee, T., Naab, R., Nagai, R., Nakos, M., Naumann, U., Necker, J., Neumann, M., Niederhausen, H., Nisa, M. U., Noell, A., Nowicki, S. C., Pollmann, A. Obertacke, Oehler, M., Oeyen, B., Olivas, A., Orsoe, R., Osborn, J., O'Sullivan, E., Pandya, H., Park, N., Parker, G. K., Paudel, E. N., Paul, L., Heros, C. Pérez de los, Peterson, J., Philippen, S., Pieper, S., Pizzuto, A., Plum, M., Popovych, Y., Rodriguez, M. Prado, Pries, B., Procter-Murphy, R., Przybylski, G. T., Raab, C., Rack-Helleis, J., Rawlins, K., Rechav, Z., Rehman, A., Reichherzer, P., Renzi, G., Resconi, E., Reusch, S., Rhode, W., Richman, M., Riedel, B., Roberts, E. J., Robertson, S., Rodan, S., Roellinghoff, G., Rongen, M., Rott, C., Ruhe, T., Ruohan, L., Ryckbosch, D., Safa, I., Saffer, J., Salazar-Gallegos, D., Sampathkumar, P., Herrera, S. E. Sanchez, Sandrock, A., Santander, M., Sarkar, S., Savelberg, J., Savina, P., Schaufel, M., Schieler, H., Schindler, S., Schlüter, B., Schmidt, T., Schneider, J., Schröder, F. G., Schumacher, L., Schwefer, G., Sclafani, S., Seckel, D., Seunarine, S., Sharma, A., Shefali, S., Shimizu, N., Silva, M., Skrzypek, B., Smithers, B., Snihur, R., Soedingrekso, J., Søgaard, A., Soldin, D., Sommani, G., Spannfellner, C., Spiczak, G. M., Spiering, C., Stamatikos, M., Stanev, T., Stein, R., Stezelberger, T., Stürwald, T., Stuttard, T., Sullivan, G. W., Taboada, I., Ter-Antonyan, S., Thompson, W. G., Thwaites, J., Tilav, S., Tollefson, K., Tönnis, C., Toscano, S., Tosi, D., Trettin, A., Tung, C. F., Turcotte, R., Twagirayezu, J. P., Ty, B., Elorrieta, M. A. Unland, Upadhyay, A. K., Upshaw, K., Valtonen-Mattila, N., Vandenbroucke, J., van Eijndhoven, N., Vannerom, D., van Santen, J., Vara, J., Veitch-Michaelis, J., Venugopal, M., Verpoest, S., Veske, D., Walck, C., Watson, T. B., Weaver, C., Weigel, P., Weindl, A., Weldert, J., Wendt, C., Werthebach, J., Weyrauch, M., Whitehorn, N., Wiebusch, C. H., Willey, N., Williams, D. R., Wolf, M., Wrede, G., Wulff, J., Xu, X. W., Yanez, J. P., Yildizci, E., Yoshida, S., Yu, F., Yu, S., Yuan, T., Zhang, Z., and Zhelnin, P.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Phenomenology
Abstract: Dark Matter particles in the Galactic Center and halo can annihilate or decay into a pair of neutrinos producing a monochromatic flux of neutrinos. The spectral feature of this signal is unique and it is not expected from any astrophysical production mechanism. Its observation would constitute a dark matter smoking gun signal. We performed the first dedicated search with a neutrino telescope for such signal, by looking at both the angular and energy information of the neutrino events. To this end, a total of five years of IceCube's DeepCore data has been used to test dark matter masses ranging from 10~GeV to 40~TeV. No significant neutrino excess was found and upper limits on the annihilation cross section, as well as lower limits on the dark matter lifetime, were set. The limits reached are of the order of $10^{-24}$~cm$^3/s$ for an annihilation and up to $10^{27}$ seconds for decaying Dark Matter. Using the same data sample we also derive limits for dark matter annihilation or decay into a pair of Standard Model charged particles.
Published: 2023

4. The Fermi-LAT Light Curve Repository

Author: Abdollahi, S., Ajello, M., Baldini, L., Ballet, J., Bastieri, D., Gonzalez, J. Becerra, Bellazzini, R., Berretta, A., Bissaldi, E., Bonino, R., Brill, A., Bruel, P., Burns, E., Buson, S., Cameron, A., Caputo, R., Caraveo, P. A., Cibrario, N., Ciprini, S., Orestano, P. Cristarella, Crnogorcevic, M., Cutini, S., D'Ammando, F., De Gaetano, S., Digel, S. W., Di Lalla, N., Di Venere, L., Domínguez, A., Ramazani, V. Fallah, Fegan, S. J., Ferrara, E. C., Fiori, A., Fleischhack, H., Franckowiak, A., Fukazawa, Y., Fusco, P., Gammaldi, V., Gargano, F., Garrappa, S., Gasbarra, C., Gasparrini, D., Giglietto, N., Giordano, F., Giroletti, M., Green, D., Grenier, I. A., Guiriec, S., Gustafsson, M., Hays, E., Horan, D., Hou, X., Jóhannesson, G., Kerr, M., Kocevski, D., Kuss, M., Latronico, L., Li, J., Liodakis, I., Longo, F., Loparco, F., Lorusso, L., Lott, B., Lovellette, M. N., Lubrano, P., Maldera, S., Manfreda, A., Mart\'-Devesa, G., Mazziotta, M. N., Mereu, I., Meyer, M., Michelson, P. F., Mizuno, T., Monzani, M. E., Morselli, A., Moskalenko, I. V., Negro, M., Omodei, N., Orlando, E., Ormes, J. F., Paneque, D., Panzarini, G., Perkins, J. S., Persic, M., Pesce-Rollins, M., Pillera, R., Porter, T. A., Principe, G., Racusin, J. L., Rainò, S., Rando, R., Rani, B., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Sánchez-Conde, M., Parkinson, P. M. Saz, Scargle, Jeff, Scotton, L., Serini, D., Sgrò, C., Siskind, E. J., Spandre, G., Spinelli, P., Suson, D. J., Tajima, H., Thompson, D. J., Torres, D. F., Valverde, J., Venters, T., Wadiasingh, Z., Wagner, S., and Wood, K.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: The Fermi Large Area Telescope (LAT) light curve repository (LCR) is a publicly available, continually updated library of gamma-ray light curves of variable Fermi-LAT sources generated over multiple timescales. The Fermi-LAT LCR aims to provide publication-quality light curves binned on timescales of 3 days, 7 days, and 30 days for 1525 sources deemed variable in the source catalog of the first 10 years of Fermi-LAT observations. The repository consists of light curves generated through full likelihood analyses that model the sources and the surrounding region, providing fluxes and photon indices for each time bin. The LCR is intended as a resource for the time-domain and multi-messenger communities by allowing users to quickly search LAT data to identify correlated variability and flaring emission episodes from gamma-ray sources. We describe the sample selection and analysis employed by the LCR and provide an overview of the associated data access portal., Comment: Accepted for publication in ApJ Supplement Series
Published: 2023
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5. Search for new cosmic-ray acceleration sites within the 4FGL catalog Galactic plane sources

Author: Collaboration, Fermi-LAT, Abdollahi, S., Acero, F., Ackermann, M., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bellazzini, R., Berenji, B., Berretta, A., Bissaldi, E., Blandford, R. D., Bonino, R., Bruel, P., Buson, S., Cameron, R. A., Caputo, R., Caraveo, P. A., Castro, D., Chiaro, G., Cibrario, N., Ciprini, S., Coronado-Blázquez, J., Crnogorcevic, M., Cutini, S., D'Ammando, F., De Gaetano, S., Di Lalla, N., Dirirsa, F., Di Venere, L., Domínguez, A., Fegan, S. J., Fiori, A., Fleischhack, H., Franckowiak, A., Fukazawa, Y., Fusco, P., Gammaldi, V., Gargano, F., Gasparrini, D., Giacchino, F., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Green, D., Grenier, I. A., Grondin, M. -H., Guiriec, S., Gustafsson, M., Harding, A. K., Hays, E., Hewitt, J. W., Horan, D., Hou, X., Jóhannesson, G., Kayanoki, T., Kerr, M., Kuss, M., Larsson, S., Latronico, L., Lemoine-Goumard, M., Li, J., Longo, F., Loparco, F., Lubrano, P., Maldera, S., Malyshev, D., Manfreda, A., Martí-Devesa, G., Mazziotta, M. N., Mereu, I., Michelson, P. F., Mirabal, N., Mitthumsiri, W., Mizuno, T., Monzani, M. E., Morselli, A., Moskalenko, I. V., Nuss, E., Omodei, N., Orienti, M., Orlando, E., Ormes, J. F., Paneque, D., Pei, Z., Persic, M., Pesce-Rollins, M., Pillera, R., Poon, H., Porter, T. A., Principe, G., Rainò, S., Rando, R., Rani, B., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Reposeur, T., Sánchez-Conde, M., Parkinson, P. M. Saz, Scotton, L., Serini, D., Sgrò, C., Siskind, E. J., Spandre, G., Spinelli, P., Sueoka, K., Suson, D. J., Tajima, H., Tak, D., Thayer, J. B., Torres, D. F., Troja, E., Valverde, J., Wadiasingh, Z., Wood, K., and Zaharijas, G.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Cosmic rays are mostly composed of protons accelerated to relativistic speeds. When those protons encounter interstellar material, they produce neutral pions which in turn decay into gamma rays. This offers a compelling way to identify the acceleration sites of protons. A characteristic hadronic spectrum, with a low-energy break around 200 MeV, was detected in the gamma-ray spectra of four Supernova Remnants (SNRs), IC 443, W44, W49B and W51C, with the Fermi Large Area Telescope. This detection provided direct evidence that cosmic-ray protons are (re-)accelerated in SNRs. Here, we present a comprehensive search for low-energy spectral breaks among 311 4FGL catalog sources located within 5 degrees from the Galactic plane. Using 8 years of data from the Fermi Large Area Telescope between 50 MeV and 1 GeV, we find and present the spectral characteristics of 56 sources with a spectral break confirmed by a thorough study of systematic uncertainty. Our population of sources includes 13 SNRs for which the proton-proton interaction is enhanced by the dense target material; the high-mass gamma-ray binary LS~I +61 303; the colliding wind binary eta Carinae; and the Cygnus star-forming region. This analysis better constrains the origin of the gamma-ray emission and enlarges our view to potential new cosmic-ray acceleration sites., Comment: Accepted for publication in The Astrophysical Journal
Published: 2022
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6. A Gamma-ray Pulsar Timing Array Constrains the Nanohertz Gravitational Wave Background

Author: Ajello, M., Atwood, W. B., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bellazzini, R., Berretta, A., Bhattacharyya, B., Bissaldi, E., Blandford, R. D., Bloom, E., Bonino, R., Bruel, P., Buehler, R., Burns, E., Buson, S., Cameron, R. A., Caraveo, P. A., Cavazzuti, E., Cibrario, N., Ciprini, S., Clark, C. J., Cognard, I., Coronado-Blázquez, J., Crnogorcevic, M., Cromartie, H., Crowter, K., Cutini, S., D'Ammando, F., Gaetano, S. D., Palma, F. d., Digel, S. W., Lalla, N. D., Dirirsa, F. Fan., Venere, L. D., Domínguez, A., Ferrara, E. C., Fiori, A., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gammaldi, V., Gargano, F., Gasparrini, D., Giglietto, N., Giordano, F., Giroletti, M., Green, D., Grenier, I. A., Guillemot, L., Guiriec, S., Gustafsson, M., Harding, A. K., Hays, E., Hewitt, J. W., Horan, D., Hou, X., Jóhannesson, G., Keith, M. J., Kerr, M., Kramer, M., Kuss, M., Larsson, S., Latronico, L., Li, J., Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., Maldera, S., Manfreda, A., Martí-Devesa, G., Mazziotta, M. N., Mereu, I., Michelson, P. F., Mirabal, N., Mitthumsiri, W., Mizuno, T., Monzani, M. E., Morselli, A., Negro, M., Nieder, L., Ojha, R., Omodei, N., Orienti, M., Orlando, E., Ormes, J. F., Paneque, D., Parthasarathy, A., Pei, Z., Persic, M., Pesce-Rollins, M., Pillera, R., Poon, H., Porter, T. A., Principe, G., Racusin, J. L., Rainò, S., Rando, R., Rani, B., Ransom, S. M., Ray, P. S., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Roy, J., Sánchez-Conde, M., Parkinson, P. M. Sa., Scargle, J., Scotton, L., Serini, D., Sgrò, C., Siskind, E. J., Smith, D. A., Spandre, G., Spiewak, R., Spinelli, P., Stairs, I., Suson, D. J., Swihart, S. J., Tabassum, S., Thayer, J. B., Theureau, G., Torres, D. F., Troja, E., Valverde, J., Wadiasingh, Z., Wood, K., and Zaharijas, G.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: After large galaxies merge, their central supermassive black holes are expected to form binary systems whose orbital motion generates a gravitational wave background (GWB) at nanohertz frequencies. Searches for this background utilize pulsar timing arrays, which perform long-term monitoring of millisecond pulsars (MSPs) at radio wavelengths. We use 12.5 years of Fermi Large Area Telescope data to form a gamma-ray pulsar timing array. Results from 35 bright gamma-ray pulsars place a 95\% credible limit on the GWB characteristic strain of $1.0\times10^{-14}$ at 1 yr$^{-1}$, which scales as the observing time span $t_{\mathrm{obs}}^{-13/6}$. This direct measurement provides an independent probe of the GWB while offering a check on radio noise models., Comment: 3 figures in the main text. 3 figures and 8 tables are in the supplementary material
Published: 2022
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7. Fermi Large Area Telescope Performance After 10 Years Of Operation

Author: The Fermi LAT Collaboration, Ajello, M., Atwood, W. B., Axelsson, M., Bagagli, R., Bagni, M., Baldini, L., Bastieri, D., Bellardi, F., Bellazzini, R., Bissaldi, E., Bloom, E. D., Bonino, R., Bregeon, J., Brez, A., Bruel, P., Buehler, R., Buson, S., Cameron, R. A., Caraveo, P. A., Cavazzuti, E., Ceccanti, M., Chen, S., Cheung, C. C., Ciprini, S., Cognard, I., Cohen-Tanugi, J., Cutini, S., D'Ammando, F., Luque, P. de la Torre, de Palma, F., Digel, S. W., Dirirsa, F., Di Lalla, N., Di Venere, L., Domínguez, A., Fabiani, D., Ferrara, E. C., Fiori, A., Foglia, G., Fukazawa, Y., Fusco, P., Gargano, F., Gasparrini, D., Giroletti, M., Glanzman, T., Green, D., Griffin, S., Grondin, M. -H., Grove, J. E., Guillemot, L., Guiriec, S., Gustafsson, M., Hays, E., Horan, D., Jóhannesson, G., Johnson, T. J., Kamae, T., Kerr, M., Kuss, M., Larsson, S., Latronico, L., Lemoine-Goumard, M., Li, J., Liodakis, I., Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., Maldera, S., Manfreda, A., Martí-Devesa, G., Mazziotta, M. N., Menon, N., Mereu, I., Meyer, M., Michelson, P. F., Minuti, M., Mitthumsiri, W., Mizuno, T., Mongelli, M., Monzani, M. E., Moskalenko, I. V., Negro, M., Nuss, E., Ojha, R., Orienti, M., Orlando, E., Paccagnella, A., Paliya, V. S., Paneque, D., Pei, Z., Perkins, J. S., Pesce-Rollins, M., Pinchera, M., Piron, F., Poon, H., Porter, T. A., Primavera, R., Principe, G., Racusin, J. L., Rainò, S., Rando, R., Rani, B., Rapposelli, E., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Russell, J. J., Saggini, N., Parkinson, P. M. Saz, Scolieri, N., Serini, D., Sgrò, C., Siskind, E. J., Smith, D. A., Spandre, G., Spinelli, P., Suson, D. J., Tajima, H., Thayer, J. G., Thompson, D. J., Tibaldo, L., Torres, D. F., Tosti, G., Valverde, J., Vigiani, L., and Zaharijas, G.
Subjects: Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: The Large Area Telescope (LAT), the primary instrument for the Fermi Gamma-ray Space Telescope (Fermi) mission, is an imaging, wide field-of-view, high-energy gamma-ray telescope, covering the energy range from 30 MeV to more than 300 GeV. We describe the performance of the instrument at the 10-year milestone. LAT performance remains well within the specifications defined during the planning phase, validating the design choices and supporting the compelling case to extend the duration of the Fermi mission. The details provided here will be useful when designing the next generation of high-energy gamma-ray observatories., Comment: 60 pages, 28 figures. Published in ApJS
Published: 2021
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8. Catalog of Long-Term Transient Sources in the First 10 Years of Fermi-LAT Data

Author: Baldini, L., Ballet, J., Bastieri, D., Gonzalez, J. Becerra, Bellazzini, R., Berretta, A., Bissaldi, E., Blandford, R. D., Bloom, E. D., Bonino, R., Bottacini, E., Bruel, P., Buson, S., Cameron, R. A., Caraveo, P. A., Cavazzuti, E., Chen, S., Chiaro, G., Ciangottini, D., Ciprini, S., Orestano, P. Cristarella, Crnogorcevic, M., Cutini, S., D'Ammando, F., Luque, P. de la Torre, de Palma, F., Digel, S. W., Di Lalla, N., Dirirsa, F., Di Venere, L., Domínguez, A., Fiori, A., Fleischhack, H., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Green, D., Grenier, I. A., Griffin, S., Guiriec, S., Gustafsson, M., Hewitt, J. W., Horan, D., Imazawa, R., Jóhannesson, G., Kerr, M., Kocevski, D., Kuss, M., Larsson, S., Latronico, L., Li, J., Liodakis, I., Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., Maldera, S., Manfreda, A., Martí-Devesa, G., Matake, H., Mazziotta, M. N., Mereu, I., Meyer, M., Mirabal, N., Mitthumsiri, W., Mizuno, T., Monzani, M. E., Morselli, A., Moskalenko, I. V., Nagasawa, S., Negro, M., Ojha, R., Orienti, M., Orlando, E., Palatiello, M., Paliya, V., Paneque, D., Pei, Z., Persic, M., Pesce-Rollins, M., Petrosian, V., Poon, H., Porter, T. A., Principe, G., Racusin, J. L., Rainò, S., Rando, R., Rani, B., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Parkinson, P. M. Saz, Scotton, L., Serini, D., Sgrò, C., Siskind, E. J., Spandre, G., Spinelli, P., Suson, D. J., Tajima, H., Tak, D., Torres, D. F., Tosti, G., Troja, E., Wood, K., Yassine, M., and Zaharijas, G.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: We present the first Fermi Large Area Telescope (LAT) catalog of long-term $\gamma$-ray transient sources (1FLT). This comprises sources that were detected on monthly time intervals during the first decade of Fermi-LAT operations. The monthly time scale allows us to identify transient and variable sources that were not yet reported in other Fermi-LAT catalogs. The monthly datasets were analyzed using a wavelet-based source detection algorithm that provided the candidate new transient sources. The search was limited to the extragalactic regions of the sky to avoid the dominance of the Galactic diffuse emission at low Galactic latitudes. The transient candidates were then analyzed using the standard Fermi-LAT Maximum Likelihood analysis method. All sources detected with a statistical significance above 4$\sigma$ in at least one monthly bin were listed in the final catalog. The 1FLT catalog contains 142 transient $\gamma$-ray sources that are not included in the 4FGL-DR2 catalog. Many of these sources (102) have been confidently associated with Active Galactic Nuclei (AGN): 24 are associated with Flat Spectrum Radio Quasars; 1 with a BL Lac object; 70 with Blazars of Uncertain Type; 3 with Radio Galaxies; 1 with a Compact Steep Spectrum radio source; 1 with a Steep Spectrum Radio Quasar; 2 with AGN of other types. The remaining 40 sources have no candidate counterparts at other wavelengths. The median $\gamma$-ray spectral index of the 1FLT-AGN sources is softer than that reported in the latest Fermi-LAT AGN general catalog. This result is consistent with the hypothesis that detection of the softest $\gamma$-ray emitters is less efficient when the data are integrated over year-long intervals., Comment: 41 pages, 17 figures, 7 tables; Accepted by ApJS on 24 May 2021; Contact Authors: I. Mereu, S. Cutini, E. Cavazzuti, G. Tosti
Published: 2021
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9. Search for dark matter signatures in the gamma-ray emission towards the Sun with the Fermi Large Area Telescope

Author: Mazziotta, M. N., Loparco, F., Serini, D., Cuoco, A., Luque, P. De La Torre, Gargano, F., and Gustafsson, M.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Experiment
Abstract: Dark matter particles from the Galactic halo can be gravitationally trapped in the solar core or in external orbits. The enhanced density of dark matter particles either in the solar core or in external orbits can result in the annihilation of these particles producing gamma rays via long-lived intermediate states or directly outside the Sun, respectively. These processes would yield characteristic features in the energy spectrum of the subsequent gamma rays, i.e., a box-like or line-like shaped feature, respectively. We have performed a dedicated analysis using a 10-years sample of gamma-ray events from the Sun collected by the Fermi Large Area Telescope searching for spectral features in the energy spectrum as a signature of dark matter annihilation. In the scenario of gamma-ray production via long-lived mediators we have also evaluated the dark matter-nucleon spin-dependent and spin-independent scattering cross section constraints from the flux limits in a dark matter mass range from 3 GeV/c$^2$ up to about 1.8 TeV/c$^2$. In the mass range up to about 150 GeV/c$^2$ the limits are in the range $10^{-46} - 10^{-45}$ cm$^{2}$ for the spin-dependent scattering and in the range $10^{-48} - 10^{-47}$ cm$^{2}$ for the spin-independent case. The range of variation depends on the decay length of the mediator., Comment: 12 pages; 7 figures; accepted by PRD
Published: 2020
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10. A search for dark matter cosmic-ray electrons and positrons from the Sun with the Fermi Large Area Telescope

Author: Cuoco, A., Luque, P. De La Torre, Gargano, F., Gustafsson, M., Loparco, F., Mazziotta, M. N., and Serini, D.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Phenomenology
Abstract: We use 7 years of electron and positron Fermi-LAT data to search for a possible excess in the direction of the Sun in the energy range from 42 GeV to 2 TeV. In the absence of a positive signal we derive flux upper limits which we use to constrain two different dark matter (DM) models producing $e^+ e^-$ fluxes from the Sun. In the first case we consider DM model being captured by the Sun due to elastic scattering and annihilation into $e^+ e^-$ pairs via a long-lived light mediator that can escape the Sun. In the second case we consider instead a model where DM density is enhanced around the Sun through inelastic scattering and the DM annihilates directly into $e^+ e^-$ pairs. In both cases we perform an optimal analysis, searching specifically for the energy spectrum expected in each case, i.e., a box-like shaped and line-like shaped spectrum respectively. No significant signal is found and we can place limits on the spin-independent cross-section in the range from $10^{-46}~cm^2$ to $10^{-44}~cm^2$ and on the spin-dependent cross-section in the range from $10^{-43}~cm^2$ to $10^{-41}~cm^2$. In the case of inelastic scattering the limits on the cross-section are in the range from $10^{-43}~cm^2$ to $10^{-41}~cm^2$. The limits depend on the life time of the mediator (elastic case) and on the mass splitting value (inelastic case), as well as on the assumptions made for the size of the deflections of electrons and positrons in the interplanetary magnetic field., Comment: 12 pages; 6 figures; Accepted by PRD for publication
Published: 2019
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11. Upper bounds on absorption and scattering

Author: Gustafsson, M., Schab, K., Jelinek, L., and Capek, M.
Subjects: Physics - Optics
Abstract: A general framework for determining fundamental bounds in nanophotonics is introduced in this paper. The theory is based on convex optimization of dual problems constructed from operators generated by electromagnetic integral equations. The optimized variable is a contrast current defined within a prescribed region of a given material constitutive relations. Two power conservation constraints analogous to optical theorem are utilized to tighten the bounds and to prescribe either losses or material properties. Thanks to the utilization of matrix rank-1 updates, modal decompositions, and model order reduction techniques, the optimization procedure is computationally efficient even for complicated scenarios. No dual gaps are observed. The method is well-suited to accommodate material anisotropy and inhomogeneity. To demonstrate the validity of the method, bounds on scattering, absorption, and extinction cross sections are derived first and evaluated for several canonical regions. The tightness of the bounds is verified by comparison to optimized spherical nanoparticles and shells. The next metric investigated is bi-directional scattering studied closely on a particular example of an electrically thin slab. Finally, the bounds are established for Purcell's factor and local field enhancement where a dimer is used as a practical example., Comment: 38 pages, 16 figures
Published: 2019
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12. Older Individuals’ Experiences of Medication Management and Care After Discharge from Hospital: An Interview Study

Author: Norberg H, Håkansson Lindqvist M, and Gustafsson M
Subjects: medication adherence, qualitative research, transitional care, shared decision making, self management, Medicine (General), R5-920
Abstract: Helena Norberg,1 Marcia Håkansson Lindqvist,2 Maria Gustafsson1 1Department of Integrative Medical Biology, Umeå University, Umeå, Sweden; 2Department of Education, Mid Sweden University, Sundsvall, SwedenCorrespondence: Helena Norberg, Department of Integrative Medical Biology, Umeå University, Umeå, S-901 87, Sweden, Tel +46 90 786 68 21, Email helena.norberg@umu.sePurpose: To develop an in-depth understanding of older individuals’ attitudes and perceptions of medication management and care after discharge from hospital-to-home.Patients and Methods: A qualitative study using semi-structured interviews with selected individuals 75 years and older, discharged from hospital within the last 6– 12 months, living at home, and managing their own medications. Face-to-face interviews were audio-recorded, transcribed and analyzed with thematic analysis.Results: Among the 15 respondents, mean age was 83.5 years (range 75– 95 years), 67% were women, and 60% lived alone. The majority (80%) managed their medications with a pill organizer or directly from the pill boxes, while 20% used dose dispensed medications. The analysis of the data led to six themes: Medication adherence, Personal responsibility, Transitions of care, Beliefs about medications, Participation (experience of participation, willingness to participate) and Accessibility (easier to reach hospital than primary care, navigating in the care system, continuity, personal chemistry).Conclusion: The included respondents who were older individuals, living at home and managing their own medications, expressed that they were medical adherent and self-managing. Two important aspects which were seen were difficulties to reach primary care on their own initiative and the lack of continuity with the same physician over a longer period of time.Keywords: medication adherence, qualitative research, transitional care, shared decision making, self management
Published: 2023

13. Maternal vitamin D status in pregnancy and molar incisor hypomineralisation and hypomineralised second primary molars in the offspring at 7–9 years of age: a longitudinal study

Author: Børsting, T., Schuller, A., van Dommelen, P., Stafne, S. N., Skeie, M. S., Skaare, A. B., Mørkved, S., Salvesen, K. Å., Stunes, A. K., Mosti, M. P., Gustafsson, M. K., Syversen, U., and Fagerhaug, T. N.
Published: 2022
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14. Hydrogen dimers in giant-planet infrared spectra

Author: Fletcher, L. N., Gustafsson, M., and Orton, G. S.
Subjects: Astrophysics - Earth and Planetary Astrophysics
Abstract: Despite being one of the weakest dimers in nature, low-spectral-resolution Voyager/IRIS observations revealed the presence of (H$_2$)$_2$ dimers on Jupiter and Saturn in the 1980s. However, the collision-induced H$_2$-H$_2$ opacity databases widely used in planetary science (Borysow et al., 1985; Orton et al., 2007; Richard et al., 2012) have thus far only included free-to-free transitions and have neglected the contributions of dimers. Dimer spectra have both fine-scale structure near the S$(0)$ and S$(1)$ quadrupole lines (354 and 587 cm$^{-1}$, respectively), and broad continuum absorption contributions up to $\pm50$ cm$^{-1}$ from the line centres. We develop a new ab initio model for the free-to-bound, bound-to-free and bound-to-bound transitions of the hydrogen dimer for a range of temperatures (40-400 K) and para-hydrogen fractions (0.25-1.0). The model is validated against low-temperature laboratory experiments, and used to simulate the spectra of the giant planets. The new collision-induced opacity database permits high-resolution (0.5-1.0 cm$^{-1}$) spectral modelling of dimer spectra near S$(0)$ and S$(1)$ in both Cassini Composite Infrared Spectrometer (CIRS) observations of Jupiter and Saturn, and in Spitzer Infrared Spectrometer (IRS) observations of Uranus and Neptune for the first time. Furthermore, the model reproduces the dimer signatures observed in Voyager/IRIS data near S$(0)$ (McKellar et al., 1984) on Jupiter and Saturn, and generally lowers the amount of para-H$_2$ (and the extent of disequilibrium) required to reproduce IRIS observations., Comment: 13 pages, 6 figures, accepted for publication in ApJ Supplement. Dimer absorption database available: https://doi.org/10.5281/zenodo.1095503
Published: 2017
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15. Primary Non-Adherence to Preventive Drugs and Associations with Beliefs About Medicines in Stroke Survivors

Author: Westberg A, Sjölander M, Glader EL, and Gustafsson M
Subjects: beliefs about medicines, preventive drugs, primary non-adherence, stroke, Medicine (General), R5-920
Abstract: Annica Westberg,1 Maria Sjölander,1 Eva-Lotta Glader,2 Maria Gustafsson1 1Department of Integrative Medical Biology, Umeå University, Umeå, 901 87, Sweden; 2Department of Public Health and Clinical Medicine, Umeå University, Umeå, 901 87, SwedenCorrespondence: Maria GustafssonDepartment of Integrative Medical Biology, Umeå University, Umeå, SE-901 87, Sweden, Email maria.gustafsson@umu.seBackground: Medication non-adherence is a common problem in clinical practice. Little is known about stroke survivors’ primary non-adherence to preventive drugs, and we hypothesised that their beliefs about medicines are associated with primary non-adherence. The objective was to describe primary non-adherence among stroke survivors and to assess associations between primary non-adherence to preventive drugs and beliefs about medicines.Methods: Questionnaires were sent to 797 individuals 3 months after stroke to assess beliefs about medicines through the Beliefs about Medicines Questionnaire (BMQ). All participants were registered in the Swedish Stroke Register (Riksstroke), and prescriptions for new preventive drugs during the hospital stay were identified through data from Riksstroke. Primary non-adherers were those who failed to fill one or more new prescriptions within 1 month of hospital discharge based on data from the Swedish Prescribed Drug Register. Differences between primary non-adherers and adherers were assessed by 2 tests and associations between the BMQ subscales and primary non-adherence were analysed using independent two-sample t-tests and multivariable logistic regression models.Results: A total of 594 individuals responded to the survey, of which 452 received new prescriptions of preventive drugs. Overall, 53 (12%) participants were classified as primary non-adherent. Primary non-adherers were more often dependent on help or support from next of kin (p=0.032) and had difficulties with memory more often (p=0.002) than the primary adherent individuals. No statistically significant differences in BMQ subscale-scores were found between the two groups (p> 0.05).Conclusion: Primary non-adherence to preventive drugs was low, and no associations were found between primary non-adherence and beliefs about medicines. Associations with cognitive impairments such as difficulties with memory and need for help from next of kin suggest that more effort is needed to help stroke survivors to start important preventive drug treatments after discharge from hospital.Keywords: beliefs about medicines, preventive drugs, primary non-adherence, stroke
Published: 2022

16. The 1st Fermi Lat Supernova Remnant Catalog

Author: Acero, Fabio, Ackermann, Markus, Ajello, Marco, Baldini, Luca, Ballet, Jean, Barbiellini, Guido, Bastieri, Denis, Bellazzini, Ronaldo, Bissaldi, E., Blandford, Roger, Bloom, E. D., Bonino, Raffaella, Bottacini, Eugenio, Bregeon, J., Bruel, Philippe, Buehler, Rolf, Buson, S., Caliandro, G. A., Cameron, Rob A., Caputo, R, Caragiulo, Micaela, Caraveo, Patrizia A., Casandjian, Jean Marc, Cavazzuti, Elisabetta, Cecchi, Claudia, Chekhtman, A., Chiang, J., Chiaro, G., Ciprini, Stefano, Claus, R., Cohen, J. M., Cohen-Tanugi, Johann, Cominsky, L. R., Condon, B., Conrad, Jan, Cutini, S., D'Ammando, F., Angelis, A., Palma, F., Desiante, Rachele, Digel, S. W., Venere, L., Drell, Persis S, Drlica-Wagner, Alex, Favuzzi, C., Ferrara, E. C., Franckowiak, Anna, Fukazawa, Prof. Yasushi, Funk, Prof. Stefan, Fusco, P., Gargano, Fabio, Gasparrini, Dario, Giglietto, Nicola, Giommi, Paolo, Giordano, Francesco, Giroletti, Marcello, Glanzman, Tom, Godfrey, Gary, Gomez-Vargas, G A., Grenier, I. A., Grondin, M. -H., Guillemot, L., Guiriec, Sylvain, Gustafsson, M, Hadasch, D., Harding, A. K., Hayashida, M., Hays, Elizabeth, Hewitt, J. W., Hill, A. B., Horan, Deirdre, Hou, X., Iafrate, Giulia, Jogler, Tobias, J'ohannesson, G., Johnson, Anthony S., Kamae, T., Katagiri, Hideaki, Kataoka, Prof. Jun, Katsuta, Junichiro, Kerr, Matthew, Knodlseder, J., Kocevski, Prof. Dale, Kuss, M., Laffon, Helene, Lande, J., Larsson, S., Latronico, Luca, Lemoine-Goumard, Marianne, Li, J., Li, L., Longo, Francesco, Loparco, Francesco, Lovellette, Michael N., Lubrano, Pasquale, Magill, J., Maldera, S., Marelli, Martino, Mayer, Michael, Mazziotta, M. N., Michelson, Peter F., Mitthumsiri, Warit, Mizuno, Tsunefumi, Moiseev, Alexander A., Monzani, Maria Elena, Moretti, E., Morselli, Aldo, Moskalenko, Igor V., Murgia, Prof. Simona, Nemmen, Prof. Rodrigo, Nuss, Eric, Ohsugi, Takashi, Omodei, Nicola, Orienti, Monica, Orlando, Elena, Ormes, Jonathan F., Paneque, David, Perkins, J. S., Pesce-Rollins, Melissa, Petrosian, Prof. Vahe', Piron, Frederic, Pivato, Giovanna, Porter, Troy, Rain`o, S., Rando, Riccardo, Razzano, Massimiliano, Razzaque, Soebur, Reimer, Anita, Reimer, Prof. Olaf, Renaud, Matthieu, Reposeur, Thierry, Rousseau, Mr. Romain, Parkinson, P. M., Schmid, J., Schulz, A., Sgr`o, C., Siskind, Eric J, Spada, Francesca, Spandre, Gloria, Spinelli, Paolo, Strong, Andrew W., Suson, Daniel, Tajima, Hiro, Takahashi, Hiromitsu, Tanaka, T., Thayer, Jana B., Thompson, D. J., Tibaldo, L., Tibolla, Omar, Torres, Prof. Diego F., Tosti, Gino, Troja, Eleonora, Uchiyama, Yasunobu, Vianello, G., Wells, B., Wood, Kent, Wood, M., Yassine, Manal, and Zimmer, Stephan
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: To uniformly determine the properties of supernova remnants (SNRs) at high energies, we have developed the first systematic survey at energies from 1 to 100 GeV using data from the Fermi Large Area Telescope. Based on the spatial overlap of sources detected at GeV energies with SNRs known from radio surveys, we classify 30 sources as likely GeV SNRs. We also report 14 marginal associations and 245 flux upper limits. A mock catalog in which the positions of known remnants are scrambled in Galactic longitude, allows us to determine an upper limit of 22% on the number of GeV candidates falsely identified as SNRs. We have also developed a method to estimate spectral and spatial systematic errors arising from the diffuse interstellar emission model, a key component of all Galactic Fermi LAT analyses. By studying remnants uniformly in aggregate, we measure the GeV properties common to these objects and provide a crucial context for the detailed modeling of individual SNRs. Combining our GeV results with multiwavelength (MW) data, including radio, X-ray, and TeV, demonstrates the need for improvements to previously sufficient, simple models describing the GeV and radio emission from these objects. We model the GeV and MW emission from SNRs in aggregate to constrain their maximal contribution to observed Galactic cosmic rays., Comment: Resubmitted to ApJS
Published: 2015
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17. Dimensions and characteristics of biogas policies – Modelling the European policy landscape

Author: Gustafsson, M. and Anderberg, S.
Published: 2021
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18. Search for Gamma-Ray Lines towards Galaxy Clusters with the Fermi-LAT

Author: Anderson, B., Zimmer, S., Conrad, J., Gustafsson, M., Sánchez-Conde, M., and Caputo, R.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Phenomenology
Abstract: We report on a search for monochromatic $\gamma$-ray features in the spectra of galaxy clusters observed by the \emph{Fermi} Large Area Telescope. Galaxy clusters are the largest structures in the Universe that are bound by dark matter (DM), making them an important testing ground for possible self-interactions or decays of the DM particles. Monochromatic $\gamma$-ray lines provide a unique signature due to the absence of astrophysical backgrounds and are as such considered a smoking-gun signature for new physics. An unbinned joint likelihood analysis of the sixteen most promising clusters using five years of data at energies between 10 and 400 GeV revealed no significant features. For the case of self-annihilation, we set upper limits on the monochromatic velocity-averaged interaction cross section. These limits are compatible with those obtained from observations of the Galactic Center, albeit weaker due to the larger distance to the studied clusters., Comment: 17 pages, 6 figures, 1 table; minor changes to match version to appear in JCAP, corresponding authors: B. Anderson & S. Zimmer
Published: 2015
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19. Search for extended gamma-ray emission from the Virgo galaxy cluster with Fermi-LAT

Author: Ackermann, M., Ajello, M., Albert, A., Atwood, W. B., Baldini, L., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Bissaldi, E., Bloom, E. D., Bonino, R., Bottacini, E., Brandt, T. J., Bregeon, J., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caputo, R., Caragiulo, M., Caraveo, P. A., Casandjian, J. M., Cavazzuti, E., Cecchi, C., Charles, E., Chekhtman, A., Chiaro, G., Ciprini, S., Cohen-Tanugi, J., Conrad, J., Cutini, S., D'Ammando, F., de Angelis, A., de Palma, F., Desiante, R., Digel, S. W., Di Venere, L., Drell, P. S., Favuzzi, C., Fegan, S. J., Focke, W. B., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Gomez-Vargas, G. A., Grenier, I. A., Guiriec, S., Gustafsson, M., Hewitt, J. W., Hill, A. B., Horan, D., Jeltema, T. E., Jogler, T., Johnson, A. S., Kuss, M., Larsson, S., Latronico, L., Li, J., Li, L., Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., Maldera, S., Malyshev, D., Manfreda, A., Mayer, M., Mazziotta, M. N., Michelson, P. F., Mizuno, T., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nuss, E., Ohsugi, T., Orienti, M., Orlando, E., Ormes, J. F., Paneque, D., Perkins, J. S., Pesce-Rollins, M., Petrosian, V., Piron, F., Pivato, G., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Reimer, A., Reimer, O., Sánchez-Conde, M., Schulz, A., Sgró, C., Siskind, E. J., Spada, F., Spandre, G., Spinelli, P., Storm, E., Tajima, H., Takahashi, H., Thayer, J. B., Torres, D. F., Tosti, G., Troja, E., Vianello, G., Wood, K. S., Wood, M., Zaharijas, G., Zimmer, S., and Pinzke, A.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Phenomenology
Abstract: Galaxy clusters are one of the prime sites to search for dark matter (DM) annihilation signals. Depending on the substructure of the DM halo of a galaxy cluster and the cross sections for DM annihilation channels, these signals might be detectable by the latest generation of $\gamma$-ray telescopes. Here we use three years of Fermi Large Area Telescope (LAT) data, which are the most suitable for searching for very extended emission in the vicinity of nearby Virgo galaxy cluster. Our analysis reveals statistically significant extended emission which can be well characterized by a uniformly emitting disk profile with a radius of 3\deg that moreover is offset from the cluster center. We demonstrate that the significance of this extended emission strongly depends on the adopted interstellar emission model (IEM) and is most likely an artifact of our incomplete description of the IEM in this region. We also search for and find new point source candidates in the region. We then derive conservative upper limits on the velocity-averaged DM pair annihilation cross section from Virgo. We take into account the potential $\gamma$-ray flux enhancement due to DM sub-halos and its complex morphology as a merging cluster. For DM annihilating into $b\overline{b}$, assuming a conservative sub-halo model setup, we find limits that are between 1 and 1.5 orders of magnitude above the expectation from the thermal cross section for $m_{\mathrm{DM}}\lesssim100\,\mathrm{GeV}$. In a more optimistic scenario, we exclude $\langle \sigma v \rangle\sim3\times10^{-26}\,\mathrm{cm^{3}\,s^{-1}}$ for $m_{\mathrm{DM}}\lesssim40\,\mathrm{GeV}$ for the same channel. Finally, we derive upper limits on the $\gamma$-ray-flux produced by hadronic cosmic-ray interactions in the inter cluster medium. We find that the volume-averaged cosmic-ray-to-thermal pressure ratio is less than $\sim6\%$., Comment: 15 pages, 11 figures, 4 tables, accepted for publication in ApJ; corresponding authors: T. Jogler, S. Zimmer & A. Pinzke
Published: 2015
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20. Search for Gamma-Ray Emission from DES Dwarf Spheroidal Galaxy Candidates with Fermi-LAT Data

Author: Collaboration, The Fermi-LAT, Collaboration, The DES, Drlica-Wagner, A., Albert, A., Bechtol, K., Wood, M., Strigari, L., Sanchez-Conde, M., Baldini, L., Essig, R., Cohen-Tanugi, J., Anderson, B., Bellazzini, R., Bloom, E. D., Caputo, R., Cecchi, C., Charles, E., Chiang, J., de Angelis, A., Funk, S., Fusco, P., Gargano, F., Giglietto, N., Giordano, F., Guiriec, S., Gustafsson, M., Kuss, M., Loparco, F., Lubrano, P., Mirabal, N., Mizuno, T., Morselli, A., Ohsugi, T., Orlando, E., Persic, M., Raino, S., Sehgal, N., Spada, F., Suson, D. J., Zaharijas, G., Zimmer, S., Abbott, T., Allam, S., Balbinot, E., Bauer, A. H., Benoit-Levy, A., Bernstein, R. A., Bernstein, G. M., Bertin, E., Brooks, D., Buckley-Geer, E., Burke, D. L., Rosell, A. Carnero, Castander, F. J., Covarrubias, R., D'Andrea, C. B., da Costa, L. N., DePoy, D. L., Desai, S., Diehl, H. T., Cunha, C. E, Eifler, T. F., Estrada, J., Evrard, A. E., Neto, A. Fausti, Fernandez, E., Finley, D. A., Flaugher, B., Frieman, J., Gaztanaga, E., Gerdes, D., Gruen, D., Gruendl, R. A., Gutierrez, G., Honscheid, K., Jain, B., James, D., Jeltema, T., Kent, S., Kron, R., Kuehn, K., Kuropatkin, N., Lahav, O., Li, T. S., Luque, E., Maia, M. A. G., Makler, M., March, M., Marshall, J., Martini, P., Merritt, K. W., Miller, C., Miquel, R., Mohr, J., Neilsen, E., Nord, B., Ogando, R., Peoples, J., Petravick, D., Pieres, A., Plazas, A. A., Queiroz, A., Romer, A. K., Roodman, A., Rykoff, E. S., Sako, M., Sanchez, E., Santiago, B., Scarpine, V., Schubnell, M., Sevilla, I., Smith, R. C., Soares-Santos, M., Sobreira, F., Suchyta, E., Swanson, M. E. C., Tarle, G., Thaler, J., Thomas, D., Tucker, D., Walker, A., Wechsler, R. H., Wester, W., Williams, P., Yanny, B., and Zuntz, J.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Astrophysics of Galaxies, High Energy Physics - Experiment
Abstract: Due to their proximity, high dark-matter content, and apparent absence of non-thermal processes, Milky Way dwarf spheroidal satellite galaxies (dSphs) are excellent targets for the indirect detection of dark matter. Recently, eight new dSph candidates were discovered using the first year of data from the Dark Energy Survey (DES). We searched for gamma-ray emission coincident with the positions of these new objects in six years of Fermi Large Area Telescope data. We found no significant excesses of gamma-ray emission. Under the assumption that the DES candidates are dSphs with dark matter halo properties similar to the known dSphs, we computed individual and combined limits on the velocity-averaged dark matter annihilation cross section for these new targets. If the estimated dark-matter content of these dSph candidates is confirmed, they will constrain the annihilation cross section to lie below the thermal relic cross section for dark matter particles with masses < 20 GeV annihilating via the b-bbar or tau+tau- channels., Comment: 9 pages, 4 figures, 1 table. Updated to published version. Readers may be interested in the related work by Ackermann et al. arXiv:1503.02641 (The Fermi-LAT Collaboration), Bechtol, Drlica-Wagner, et al. arXiv:1503.02584 (The DES Collaboration), and Koposov, Belokurov, Torrealba, & Evans arXiv:1503.02079
Published: 2015
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21. Limits on Dark Matter Annihilation Signals from the Fermi LAT 4-year Measurement of the Isotropic Gamma-Ray Background

Author: The Fermi LAT Collaboration, Ackermann, M., Ajello, M., Albert, A., Baldini, L., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Bissaldi, E., Bloom, E. D., Bonino, R., Bregeon, J., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caragiulo, M., Caraveo, P. A., 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., Drell, P. S., Drlica-Wagner, A., Favuzzi, C., Ferrara, E. C., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Giglietto, N., Giordano, F., Giroletti, M., Godfrey, G., Guiriec, S., Gustafsson, M., Hewitt, J. W., Hou, X., Kamae, T., Kuss, M., Larsson, S., Latronico, L., Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., Malyshev, D., Massaro, F., Mayer, M., Mazziotta, M. N., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Negro, M., Nemmen, R., Nuss, E., Ohsugi, T., Orienti, M., Orlando, E., Ormes, J. F., Paneque, D., Perkins, J. S., Pesce-Rollins, M., Piron, F., Pivato, G., Raino, S., Rando, R., Razzano, M., Reimer, A., Reimer, O., Sanchez-Conde, M., Schulz, A., Sgro, C., Siskind, E. J., Spandre, G., Spinelli, P., Strong, A. W., Suson, D. J., Tajima, H., Takahashi, H., Thayer, J. G., Thayer, J. B., Tibaldo, L., Tinivella, M., Torres, D. F., Troja, E., Uchiyama, Y., Vianello, G., Werner, M., Winer, B. L., Wood, K. S., Wood, M., and Zaharijas, G.
Subjects: Astrophysics - Cosmology and Nongalactic Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract: We search for evidence of dark matter (DM) annihilation in the isotropic gamma-ray background (IGRB) measured with 50 months of Fermi Large Area Telescope (LAT) observations. An improved theoretical description of the cosmological DM annihilation signal, based on two complementary techniques and assuming generic weakly interacting massive particle (WIMP) properties, renders more precise predictions compared to previous work. More specifically, we estimate the cosmologically-induced gamma-ray intensity to have an uncertainty of a factor ~20 in canonical setups. We consistently include both the Galactic and extragalactic signals under the same theoretical framework, and study the impact of the former on the IGRB spectrum derivation. We find no evidence for a DM signal and we set limits on the DM-induced isotropic gamma-ray signal. Our limits are competitive for DM particle masses up to tens of TeV and, indeed, are the strongest limits derived from Fermi LAT data at TeV energies. This is possible thanks to the new Fermi LAT IGRB measurement, which now extends up to an energy of 820 GeV. We quantify uncertainties in detail and show the potential this type of search offers for testing the WIMP paradigm with a complementary and truly cosmological probe of DM particle signals., Comment: Matches the JCAP published version. Corresponding authors: A. Franckowiak (afrancko@slac.stanford.edu), M. Gustafsson (michael.gustafsson@theorie.physik.uni-goettingen.de), M.A. Sanchez-Conde (sanchezconde@fysik.su.se), G. Zaharijas (gabrijela.zaharijas@ung.si)
Published: 2015
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22. The Origin of the Extragalactic Gamma-Ray Background and Implications for Dark-Matter Annihilation

Author: Ajello, M., Gasparrini, D., Sanchez-Conde, M., Zaharijas, G., Gustafsson, M., Cohen-Tanugi, J., Dermer, C. D., Inoue, Y., Hartmann, D., Ackermann, M., Bechtol, K., Franckowiak, A., Reimer, A., Romani, R. W., and Strong, A. W.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: The origin of the extragalactic $\gamma$-ray background (EGB) has been debated for some time. { The EGB comprises the $\gamma$-ray emission from resolved and unresolved extragalactic sources, such as blazars, star-forming galaxies and radio galaxies, as well as radiation from truly diffuse processes.} This letter focuses on the blazar source class, the most numerous detected population, and presents an updated luminosity function and spectral energy distribution model consistent with the blazar observations performed by the {\it Fermi} Large Area Telescope (LAT). We show that blazars account for 50$^{+12}_{-11}$\,\% of the EGB photons ($>$0.1\,GeV), and that {\it Fermi}-LAT has already resolved $\sim$70\,\% of this contribution. Blazars, and in particular low-luminosity hard-spectrum nearby sources like BL Lacs, are responsible for most of the EGB emission above 100\,GeV. We find that the extragalactic background light, which attenuates blazars' high-energy emission, is responsible for the high-energy cut-off observed in the EGB spectrum. Finally, we show that blazars, star-forming galaxies and radio galaxies can naturally account for the amplitude and spectral shape of the background in the 0.1--820\,GeV range, leaving only modest room for other contributions. This allows us to set competitive constraints on the dark-matter annihilation cross section., Comment: On behalf of the Fermi-LAT collaboration. Contact authors: M. Ajello, D. Gasparrini, M. Sanchez-Conde, G. Zaharijas, M. Gustafsson. Accepted for publication on ApJL
Published: 2015
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23. Physical and chemical properties of non-exhaust particles generated from wear between pavements and tyres

Author: Alves, C.A., Vicente, A.M.P., Calvo, A.I., Baumgardner, D., Amato, F., Querol, X., Pio, C., and Gustafsson, M.
Published: 2020
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24. 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
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25. The Third Fermi Large Area Telescope Catalog of Gamma-Ray Pulsars

Author: Smith, D. A., primary, Abdollahi, S., additional, Ajello, M., additional, Bailes, M., additional, Baldini, L., additional, Ballet, J., additional, Baring, M. G., additional, Bassa, C., additional, Gonzalez, J. Becerra, additional, Bellazzini, R., additional, Berretta, A., additional, Bhattacharyya, B., additional, Bissaldi, E., additional, Bonino, R., additional, Bottacini, E., additional, Bregeon, J., additional, Bruel, P., additional, Burgay, M., additional, Burnett, T. H., additional, Cameron, R. A., additional, Camilo, F., additional, Caputo, R., additional, Caraveo, P. A., additional, Cavazzuti, E., additional, Chiaro, G., additional, Ciprini, S., additional, Clark, C. J., additional, Cognard, I., additional, Corongiu, A., additional, Orestano, P. Cristarella, additional, Crnogorcevic, M., additional, Cuoco, A., additional, Cutini, S., additional, D’Ammando, F., additional, de Angelis, A., additional, DeCesar, M. E., additional, De Gaetano, S., additional, de Menezes, R., additional, Deneva, J., additional, de Palma, F., additional, Di Lalla, N., additional, Dirirsa, F., additional, Di Venere, L., additional, Domínguez, A., additional, Dumora, D., additional, Fegan, S. J., additional, Ferrara, E. C., additional, Fiori, A., additional, Fleischhack, H., additional, Flynn, C., additional, Franckowiak, A., additional, Freire, P. C. C., additional, Fukazawa, Y., additional, Fusco, P., additional, Galanti, G., additional, Gammaldi, V., additional, Gargano, F., additional, Gasparrini, D., additional, Giacchino, F., additional, Giglietto, N., additional, Giordano, F., additional, Giroletti, M., additional, Green, D., additional, Grenier, I. A., additional, Guillemot, L., additional, Guiriec, S., additional, Gustafsson, M., additional, Harding, A. K., additional, Hays, E., additional, Hewitt, J. W., additional, Horan, D., additional, Hou, X., additional, Jankowski, F., additional, Johnson, R. P., additional, Johnson, T. J., additional, Johnston, S., additional, Kataoka, J., additional, Keith, M. J., additional, Kerr, M., additional, Kramer, M., additional, Kuss, M., additional, Latronico, L., additional, Lee, S.-H., additional, Li, D., additional, Li, J., additional, Limyansky, B., additional, Longo, F., additional, Loparco, F., additional, Lorusso, L., additional, Lovellette, M. N., additional, Lower, M., additional, Lubrano, P., additional, Lyne, A. G., additional, Maan, Y., additional, Maldera, S., additional, Manchester, R. N., additional, Manfreda, A., additional, Marelli, M., additional, Martí-Devesa, G., additional, Mazziotta, M. N., additional, McEnery, J. E., additional, Mereu, I., additional, Michelson, P. F., additional, Mickaliger, M., additional, Mitthumsiri, W., additional, Mizuno, T., additional, Moiseev, A. A., additional, Monzani, M. E., additional, Morselli, A., additional, Negro, M., additional, Nemmen, R., additional, Nieder, L., additional, Nuss, E., additional, Omodei, N., additional, Orienti, M., additional, Orlando, E., additional, Ormes, J. F., additional, Palatiello, M., additional, Paneque, D., additional, Panzarini, G., additional, Parthasarathy, A., additional, Persic, M., additional, Pesce-Rollins, M., additional, Pillera, R., additional, Poon, H., additional, Porter, T. A., additional, Possenti, A., additional, Principe, G., additional, Rainò, S., additional, Rando, R., additional, Ransom, S. M., additional, Ray, P. S., additional, Razzano, M., additional, Razzaque, S., additional, Reimer, A., additional, Reimer, O., additional, Renault-Tinacci, N., additional, Romani, R. W., additional, Sánchez-Conde, M., additional, Parkinson, P. M. Saz, additional, Scotton, L., additional, Serini, D., additional, Sgrò, C., additional, Shannon, R., additional, Sharma, V., additional, Shen, Z., additional, Siskind, E. J., additional, Spandre, G., additional, Spinelli, P., additional, Stappers, B. W., additional, Stephens, T. E., additional, Suson, D. J., additional, Tabassum, S., additional, Tajima, H., additional, Tak, D., additional, Theureau, G., additional, Thompson, D. J., additional, Tibolla, O., additional, Torres, D. F., additional, Valverde, J., additional, Venter, C., additional, Wadiasingh, Z., additional, Wang, N., additional, Wang, P., additional, Weltevrede, P., additional, Wood, K., additional, Yan, J., additional, Zaharijas, G., additional, Zhang, C., additional, and Zhu, W., additional
Published: 2023
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26. Non-equilibrium probing of two-level charge fluctuators using the step response of a single electron transistor

Author: Pourkabirian, A., Gustafsson, M. V., Johansson, G., Clarke, J., and Delsing, P.
Subjects: Condensed Matter - Mesoscale and Nanoscale Physics
Abstract: We report a new method to study two level fluctuators (TLFs) by measuring the offset charge induced after applying a sudden step voltage to the gate electrode of a single electron transistor. The offset charge is measured for more than 20 hours for samples made on three different substrates. We find that the offset charge drift follows a logarithmic increase over four orders of magnitude in time and that the logarithmic slope increases linearly with the step voltage. The charge drift is independent of temperature, ruling out thermally activated TLFs and demonstrating that the charge fluctuations involve tunneling. These observations are in agreement with expectations for an ensemble of TLFs driven out of equilibrium. From our model, we extract the density of TLFs assuming either a volume density or a surface density., Comment: 5 pages, 5 figures
Published: 2014
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27. Inferred cosmic-ray spectrum from ${\it Fermi}$-LAT $\gamma$-ray observations of the Earth's limb

Author: Collaboration, Fermi-LAT, Ackermann, M., Ajello, M., Albert, A., Allafort, A., Baldini, L., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Blandford, R. D., Bloom, E. D., Bonamente, E., Bottacini, E., Bouvier, A., Brandt, T. J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Cecchi, C., Charles, E., Chaves, R. C. G., Chekhtman, A., Chiang, J., Chiaro, G., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Cutini, S., Dalton, M., D'Ammando, F., de Angelis, A., de Palma, F., Dermer, C. D., Digel, S. W., Di Venere, L., Silva, E. do Couto e, Drell, P. S., Drlica-Wagner, A., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Focke, W. B., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Gomez-Vargas, G. A., Grenier, I. A., Grove, J. E., Guiriec, S., Gustafsson, M., Hadasch, D., Hanabata, Y., Harding, A. K., Hayashida, M., Hayashi, K., Hewitt, J. W., Horan, D., Hou, X., Hughes, R. E., Inoue, Y., Jackson, M. S., Jogler, T., Jóhannesson, G., Johnson, A. S., Kamae, T., Kawano, T., Knödlseder, J., 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., Mehault, J., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nemmen, R., Nuss, E., Ohsugi, T., Okumura, A., Orienti, M., Orlando, E., Ormes, J. F., Paneque, D., Panetta, J. H., Perkins, J. S., Pesce-Rollins, M., Piron, F., Pivato, G., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Ritz, S., Roth, M., Schaal, M., Schulz, A., Sgrò, C., Siskind, E. J., Spandre, G., Spinelli, P., Strong, A. W., Takahashi, H., Takeuchi, Y., Thayer, J. G., Thayer, J. B., Thompson, D. J., Tibaldo, L., Tinivella, M., Torres, D. F., Tosti, G., Troja, E., Tronconi, V., Usher, T. L., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Werner, M., Winer, B. L., Wood, K. S., Wood, M., and Yang, Z.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Recent accurate measurements of cosmic-ray (CR) species by ATIC-2, CREAM, and PAMELA reveal an unexpected hardening in the proton and He spectra above a few hundred GeV, a gradual softening of the spectra just below a few hundred GeV, and a harder spectrum of He compared to that of protons. These newly-discovered features may offer a clue to the origin of high-energy CRs. We use the ${\it Fermi}$ Large Area Telescope observations of the $\gamma$-ray emission from the Earth's limb for an indirect measurement of the local spectrum of CR protons in the energy range $\sim 90~$GeV-$6~$TeV (derived from a photon energy range $15~$GeV-$1~$TeV). Our analysis shows that single power law and broken power law spectra fit the data equally well and yield a proton spectrum with index $2.68 \pm 0.04$ and $2.61 \pm 0.08$ above $\sim 200~$GeV, respectively., Comment: Accepted by PRL for publication; Contact authors: Stefan Funk, Warit Mitthumsiri, Igor Moskalenko; 2 figures
Published: 2014

28. SEARCH FOR EXTENDED GAMMA-RAY EMISSION FROM THE VIRGO GALAXY CLUSTER WITH FERMI-LAT

Author: Ackermann, M, Ajello, M, Albert, A, Atwood, WB, Baldini, L, Barbiellini, G, Bastieri, D, Bechtol, K, Bellazzini, R, Bissaldi, E, Bloom, ED, Bonino, R, Bottacini, E, Brandt, TJ, Bregeon, J, Bruel, P, Buehler, R, Buson, S, Caliandro, GA, Cameron, RA, Caputo, R, Caragiulo, M, Caraveo, PA, Casandjian, JM, Cavazzuti, E, Cecchi, C, Charles, E, Chekhtman, A, Chiaro, G, Ciprini, S, Cohen-Tanugi, J, Conrad, J, Cutini, S, D’Ammando, F, de Angelis, A, de Palma, F, Desiante, R, Digel, SW, Di Venere, L, Drell, PS, Favuzzi, C, Fegan, SJ, Focke, WB, Franckowiak, A, Fukazawa, Y, Funk, S, Fusco, P, Gargano, F, Gasparrini, D, Giglietto, N, Giordano, F, Giroletti, M, Glanzman, T, Godfrey, G, Gomez-Vargas, GA, Grenier, IA, Guiriec, S, Gustafsson, M, Hewitt, JW, Hill, AB, Horan, D, Jeltema, TE, Jogler, T, Johnson, AS, Kuss, M, Larsson, S, Latronico, L, Li, J, Li, L, Longo, F, Loparco, F, Lovellette, MN, Lubrano, P, Maldera, S, Malyshev, D, Manfreda, A, Mayer, M, Mazziotta, MN, Michelson, PF, Mizuno, T, Monzani, ME, Morselli, A, Moskalenko, IV, Murgia, S, Nuss, E, Ohsugi, T, Orienti, M, Orlando, E, Ormes, JF, Paneque, D, Perkins, JS, Pesce-Rollins, M, Petrosian, V, Piron, F, Pivato, G, Porter, TA, Rainó, S, Rando, R, Razzano, M, and Reimer, A
Subjects: galaxies: clusters: individual, gamma-rays: galaxies: clusters, gamma-rays: general, astro-ph.HE, hep-ph, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Physical Chemistry (incl. Structural), Astronomy & Astrophysics
Abstract: Galaxy clusters are one of the prime sites to search for dark matter (DM) annihilation signals. Depending on the substructure of the DM halo of a galaxy cluster and the cross sections for DM annihilation channels, these signals might be detectable by the latest generation of γ-ray telescopes. Here we use three years of Fermi-Large Area Telescope data, which are the most suitable for searching for very extended emission in the vicinity of the nearby Virgo galaxy cluster. Our analysis reveals statistically significant extended emission which can be well characterized by a uniformly emitting disk profile with a radius of 3 that moreover is offset from the cluster center. We demonstrate that the significance of this extended emission strongly depends on the adopted interstellar emission model (IEM) and is most likely an artifact of our incomplete description of the IEM in this region. We also search for and find new point source candidates in the region. We then derive conservative upper limits on the velocity-averaged DM pair annihilation cross section from Virgo. We take into account the potential γ-ray flux enhancement due to DM sub-halos and its complex morphology as a merging cluster. For DM annihilating into assuming a conservative sub-halo model setup, we find limits that are between 1 and 1.5 orders of magnitude above the expectation from the thermal cross section for mDM ≲ 100 GeV. In a more optimistic scenario, we exclude for mDM ≲ 40 GeV for the same channel. Finally, we derive upper limits on the γ-ray-flux produced by hadronic cosmic-ray interactions in the inter cluster medium. We find that the volume-averaged cosmic-ray-to-thermal pressure ratio is less than ∼6%.
Published: 2015

29. Updated search for spectral lines from Galactic dark matter interactions with pass 8 data from the Fermi Large Area Telescope

Author: Ackermann, M, Ajello, M, Albert, A, Anderson, B, Atwood, WB, Baldini, L, Barbiellini, G, Bastieri, D, Bellazzini, R, Bissaldi, E, Blandford, RD, Bloom, ED, Bonino, R, Bottacini, E, Brandt, TJ, Bregeon, J, Bruel, P, Buehler, R, Buson, S, Caliandro, GA, Cameron, RA, Caputo, R, Caragiulo, M, Caraveo, PA, 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, Desiante, R, Digel, SW, Di Venere, L, Drell, PS, Drlica-Wagner, A, Favuzzi, C, Fegan, SJ, Franckowiak, A, Fukazawa, Y, Funk, S, Fusco, P, Gargano, F, Gasparrini, D, Giglietto, N, Giordano, F, Giroletti, M, Godfrey, G, Gomez-Vargas, GA, Grenier, IA, Grove, JE, Guiriec, S, Gustafsson, M, Hewitt, JW, Hill, AB, Horan, D, Jóhannesson, G, Johnson, RP, Kuss, M, Larsson, S, Latronico, L, Li, J, Li, L, Longo, F, Loparco, F, Lovellette, MN, Lubrano, P, Malyshev, D, Mayer, M, Mazziotta, MN, McEnery, JE, Michelson, PF, Mizuno, T, Moiseev, AA, Monzani, ME, Morselli, A, Murgia, S, Nuss, E, Ohsugi, T, Orienti, M, Orlando, E, Ormes, JF, Paneque, D, Pesce-Rollins, M, Piron, F, Pivato, G, Rainò, S, Rando, R, Razzano, M, Reimer, A, Reposeur, T, Ritz, S, and Sánchez-Conde, M
Subjects: Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Quantum Physics, Nuclear & Particles Physics, Atomic, Molecular, Nuclear, Particle and Plasma Physics
Abstract: Dark matter in the Milky Way may annihilate directly into γ rays, producing a monoenergetic spectral line. Therefore, detecting such a signature would be strong evidence for dark matter annihilation or decay. We search for spectral lines in the Fermi Large Area Telescope observations of the Milky Way halo in the energy range 200 MeV-500 GeV using analysis methods from our most recent line searches. The main improvements relative to previous works are our use of 5.8 years of data reprocessed with the Pass 8 event-level analysis and the additional data resulting from the modified observing strategy designed to increase exposure of the Galactic center region. We search in five sky regions selected to optimize sensitivity to different theoretically motivated dark matter scenarios and find no significant detections. In addition to presenting the results from our search for lines, we also investigate the previously reported tentative detection of a line at 133 GeV using the new Pass 8 data.
Published: 2015

30. Dark Matter Constraints from Observations of 25 Milky Way Satellite Galaxies with the Fermi Large Area Telescope

Author: Collaboration, The Fermi-LAT, Ackermann, M., Albert, A., Anderson, B., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Bissaldi, E., Bloom, E. D., Bonamente, E., Bouvier, A., Brandt, T. J., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caragiulo, M., Caraveo, P. A., Cecchi, C., Charles, E., Chekhtman, A., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., D'Ammando, F., de Angelis, A., Dermer, C. D., Digel, S. W., Silva, E. do Couto e, Drell, P. S., Drlica-Wagner, A., Essig, R., Favuzzi, C., Ferrara, E. C., Franckowiak, A., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Giglietto, N., Giroletti, M., Godfrey, G., Gomez-Vargas, G. A., Grenier, I. A., Guiriec, S., Gustafsson, M., Hayashida, M., Hays, E., Hewitt, J., Hughes, R. E., Jogler, T., Kamae, T., Knödlseder, J., Kocevski, D., Kuss, M., Larsson, ., Latronico, L., Garde, M. Llena, Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., Martinez, G., Mayer, M., Mazziotta, M. N., 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., Orlando, E., Ormes, J. F., Perkins, J. S., Piron, F., Pivato, G., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Ritz, S., Sànchez-Conde, M., Sehgal, N., Sgrò, C., Siskind, E. J., Spinelli, P., Strigari, L., Suson, D. J., Tajima, H., Takahashi, H., Thayer, J. B., Tibaldo, L., Tinivella, M., Torres, D. F., Uchiyama, Y., Usher, T. L., Vandenbroucke, J., Vianello, G., Vitale, V., Werner, M., Winer, B. L., Wood, K. S., Wood, M., Zaharijas, G., and Zimmer, S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Experiment
Abstract: The dwarf spheroidal satellite galaxies of the Milky Way are some of the most dark-matter-dominated objects known. Due to their proximity, high dark matter content, and lack of astrophysical backgrounds, dwarf spheroidal galaxies are widely considered to be among the most promising targets for the indirect detection of dark matter via gamma rays. Here we report on gamma-ray observations of 25 Milky Way dwarf spheroidal satellite galaxies based on 4 years of Fermi Large Area Telescope (LAT) data. None of the dwarf galaxies are significantly detected in gamma rays, and we present gamma-ray flux upper limits between 500 MeV and 500 GeV. We determine the dark matter content of 18 dwarf spheroidal galaxies from stellar kinematic data and combine LAT observations of 15 dwarf galaxies to constrain the dark matter annihilation cross section. We set some of the tightest constraints to date on the the annihilation of dark matter particles with masses between 2 GeV and 10 TeV into prototypical Standard Model channels. We find these results to be robust against systematic uncertainties in the LAT instrument performance, diffuse gamma-ray background modeling, and assumed dark matter density profile., Comment: 47 pages, 8 figure, and 8 tables. Contact authors: Johann Cohen-Tanugi, Jan Conrad, Alex Drlica-Wagner, Maja Llena Garde, and Nicola Mazziotta
Published: 2013
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31. Search for cosmic-ray induced gamma-ray emission in Galaxy Clusters

Author: Ackermann, M., Ajello, M., Albert, A., Allafort, A., Atwood, W. B., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Bloom, E. D., Bonamente, E., Bottacini, E., Brandt, T. J., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Cavazzuti, E., Chaves, R. C. G., Chiang, J., Chiaro, G., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., D'Ammando, F., de Angelis, A., de Palma, F., Dermer, C. D., Digel, S. W., Drell, P. S., Drlica-Wagner, A., Favuzzi, C., Franckowiak, A., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Godfrey, G., Gomez-Vargas, G. A., Grenier, I. A., Guiriec, S., Gustafsson, M., Hadasch, D., Hayashida, M., Hewitt, J., Hughes, R. E., Jeltema, T. E., Jóhannesson, G., Johnson, A. S., Kamae, T., Kataoka, J., Knödlseder, J., Kuss, M., Lande, J., Larsson, S., Latronico, L., Garde, M. Llena, Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., 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., Orienti, M., Orlando, E., Ormes, J. F., Perkins, J. S., Pesce-Rollins, M., Piron, F., Pivato, G., Rainò, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Ruan, J., Sánchez-Conde, M., Schulz, A., Sgrò, C., Siskind, E. J., Spandre, G., Spinelli, P., Storm, E., Strong, A. W., Suson, D. J., Takahashi, H., Thayer, J. G., Thayer, J. B., Thompson, D. J., Tibaldo, L., Tinivella, M., Torres, D. F., Troja, E., Uchiyama, Y., Usher, T. L., Vandenbroucke, J., Vianello, G., Vitale, V., Winer, B. L., Wood, K. S., Zimmer, S., Pfrommer, C., and Pinzke, A.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract: Current theories predict relativistic hadronic particle populations in clusters of galaxies in addition to the already observed relativistic leptons. In these scenarios hadronic interactions give rise to neutral pions which decay into $\gamma$ rays, that are potentially observable with the Large Area Telescope (LAT) on board the Fermi space telescope. We present a joint likelihood analysis searching for spatially extended $\gamma$-ray emission at the locations of 50 galaxy clusters in 4 years of Fermi-LAT data under the assumption of the universal cosmic-ray model proposed by Pinzke & Pfrommer (2010). We find an excess at a significance of $2.7\sigma$ which upon closer inspection is however correlated to individual excess emission towards three galaxy clusters: Abell 400, Abell 1367 and Abell 3112. We discuss these cases in detail and conservatively attribute the emission to unmodeled background (for example, radio galaxies within the clusters). Through the combined analysis of 50 clusters we exclude hadronic injection efficiencies in simple hadronic models above 21% and establish limits on the cosmic-ray to thermal pressure ratio within the virial radius, $R_{200}$, to be below 1.2-1.4% depending on the morphological classification. In addition we derive new limits on the $\gamma$-ray flux from individual clusters in our sample., Comment: Manuscript version accepted for publication in ApJ with expanded set of CR models now including thermal ICM and flat CR profiles; 27 pages, 19 figures, 9 tables; Corresponding authors: S. Zimmer, zimmer@fysik.su.se; J. Conrad, conrad@fysik.su.se; C. Pfrommer, christoph.pfrommer@h-its.org; A. Pinzke, apinzke@fysik.su.se; O. Reimer, olr@slac.stanford.edu
Published: 2013
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32. GeV Observations of Star-forming Galaxies with \textit{Fermi} LAT

Author: Fermi LAT Collaboration, Ackermann, M., Ajello, M., Allafort, A., Baldini, L., Ballet, J., Bastieri, D., Bechtol, K., Bellazzini, R., Berenji, B., 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., Casandjian, J. M., Cecchi, C., Charles, E., Chekhtman, A., Cheung, C. C., Chiang, J., Cillis, A. N., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Cutini, S., De Palma, F., Dermer, C. D., Digel, S. W., Silva, E. Do Couto e, Drell, P. S., Drlica-Wagner, A., Favuzzi, C., Fegan, S. J., Fortin, P., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Germani, S., Giglietto, N., Giordano, F., Glanzman, T., Godfrey, G., Grenier, I. A., Guiriec, S., Gustafsson, M., Hadasch, D., Hayashida, M., Hays, E., Hughes, R. E., Jóhannesson, G., Johnson, A. S., Kamae, T., Katagiri, H., Kataoka, J., Knödlseder, J., Kuss, M., Lande, J., Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Martin, P., Mazziotta, M. N., McEnery, J. E., Michelson, P. F., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nishino, S., Norris, J. P., Nuss, E., Ohno, M., Ohsugi, T., Okumura, A., Omodei, N., Orlando, E., Ozaki, M., Parent, D., Persic, M., Pesce-Rollins, M., Petrosian, V., Pierbattista, M., Piron, F., Pivato, G., Porter, T. A., Rainò, S., Rando, R., Razzano, M., Reimer, A., Reimer, O., Ritz, S., Roth, M., Sbarra, C., Sgrò, C., Siskind, E. J., Spandre, G., Spinelli, P., Stawarz, \{L}ukasz, Strong, A. W., Takahashi, H., Tanaka, T., Thayer, J. B., Tibaldo, L., Tinivella, M., Torres, D. F., Tosti, G., Troja, E., Uchiyama, Y., Vandenbroucke, J., Vianello, G., Vitale, V., Waite, A. P., Wood, M., and Yang, Z.
Subjects: Astrophysics - High Energy Astrophysical Phenomena
Abstract: Recent detections of the starburst galaxies M82 and NGC 253 by gamma-ray telescopes suggest that galaxies rapidly forming massive stars are more luminous at gamma-ray energies compared to their quiescent relatives. Building upon those results, we examine a sample of 69 dwarf, spiral, and luminous and ultraluminous infrared galaxies at photon energies 0.1-100 GeV using 3 years of data collected by the Large Area Telescope (LAT) on the \textit{Fermi Gamma-ray Space Telescope} (\textit{Fermi}). Measured fluxes from significantly detected sources and flux upper limits for the remaining galaxies are used to explore the physics of cosmic rays in galaxies. We find further evidence for quasi-linear scaling relations between gamma-ray luminosity and both radio continuum luminosity and total infrared luminosity which apply both to quiescent galaxies of the Local Group and low-redshift starburst galaxies (conservative $P$-values $\lesssim0.05$ accounting for statistical and systematic uncertainties). The normalizations of these scaling relations correspond to luminosity ratios of $\log(L_{0.1-100 \rm{GeV}}/L_{1.4 \rm{GHz}}) = 1.7 \pm 0.1_{\rm (statistical)} \pm 0.2_{\rm (dispersion)}$ and $\log(L_{0.1-100 \rm{GeV}}/L_{8-1000 \mu\rm{m}}) = -4.3 \pm 0.1_{\rm (statistical)} \pm 0.2_{\rm (dispersion)}$ for a galaxy with a star formation rate of 1 $M_{\odot}$ yr$^{-1}$, assuming a Chabrier initial mass function. Using the relationship between infrared luminosity and gamma-ray luminosity, the collective intensity of unresolved star-forming galaxies at redshifts $0
Published: 2012
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33. Constraints on the Galactic Halo Dark Matter from Fermi-LAT Diffuse Measurements

Author: collaboration, The Fermi-LAT, Ackermann, M., Ajello, M., Atwood, W. B., Baldini, L., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Blandford, R. D., Bloom, E. D., Bonamente, E., 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., Charles, E., Chekhtman, A., Chiang, J., 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., Silva, E. do Couto e, Drell, P. S., Drlica-Wagner, A., Falletti, L., Favuzzi, C., Fegan, S. J., Focke, W. B., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Guiriec, S., Gustafsson, M., Hadasch, D., Hayashida, M., Horan, D., Hughes, R. E., Jackson, M. S., Jogler, T., Jóhannesson, G., Johnson, A. S., Kamae, T., Knödlseder, J., Kuss, M., Lande, J., Latronico, L., Lionetto, A. M., Garde, M. Llena, Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Mazziotta, M. N., McEnery, J. E., Mehault, J., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Naumann-Godo, M., Norris, J. P., Nuss, E., Ohsugi, T., Orienti, M., Orlando, E., Ormes, J. F., Paneque, D., Panetta, J. H., Pesce-Rollins, M., Pierbattista, M., Piron, F., Pivato, G., Poon, H., Rainò, S., Rando, R., Razzano, M., Razzaque, S., Reimer, A., Reimer, O., Romoli, C., Sbarra, C., Scargle, J. D., Sgrò, C., Siskind, E. J., Spandre, G., Spinelli, P., Stawarz, Łukasz, Strong, A. W., Suson, D. J., Tajima, H., Takahashi, H., Tanaka, T., Thayer, J. G., Thayer, J. B., Tibaldo, L., Tinivella, M., Tosti, G., Troja, E., Usher, T. L., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Waite, A. P., Wallace, E., Wood, K. S., Wood, M., Yang, Z., Zaharijas, G., and Zimmer, S.
Subjects: Astrophysics - Cosmology and Extragalactic Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract: We have performed an analysis of the diffuse gamma-ray emission with the Fermi Large Area Telescope in the Milky Way Halo region searching for a signal from dark matter annihilation or decay. In the absence of a robust dark matter signal, constraints are presented. We consider both gamma rays produced directly in the dark matter annihilation/decay and produced by inverse Compton scattering of the e+e- produced in the annihilation/decay. Conservative limits are derived requiring that the dark matter signal does not exceed the observed diffuse gamma-ray emission. A second set of more stringent limits is derived based on modeling the foreground astrophysical diffuse emission using the GALPROP code. Uncertainties in the height of the diffusive cosmic-ray halo, the distribution of the cosmic-ray sources in the Galaxy, the index of the injection cosmic-ray electron spectrum and the column density of the interstellar gas are taken into account using a profile likelihood formalism, while the parameters governing the cosmic-ray propagation have been derived from fits to local cosmic-ray data. The resulting limits impact the range of particle masses over which dark matter thermal production in the early Universe is possible, and challenge the interpretation of the PAMELA/Fermi-LAT cosmic ray anomalies as annihilation of dark matter., Comment: 23 pages, 7 figures, 3 tables. Contact authors: Jan Conrad, Alessandro Cuoco, Zhaoyu Yang, Gabrijela Zaharijas; v2: matches version published on ApJ
Published: 2012
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34. Fermi LAT Search for Dark Matter in Gamma-ray Lines and the Inclusive Photon Spectrum

Author: Collaboration, Fermi-LAT, Ackermann, M., Ajello, M., Albert, A., Baldini, L., Barbiellini, G., Bechtol, K., Bellazzini, R., Berenji, B., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Brigida, M., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Charles, E., Chekhtman, A., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., D'Ammando, F., de Palma, F., Dermer, C. D., Silva, E. do Couto e, Drell, P. S., Drlica-Wagner, A., Edmonds, Y., Essig, R., Favuzzi, C., Fegan, S. J., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Guiriec, S., Gustafsson, M., Hadasch, D., Hayashida, M., Horan, D., Hughes, R. E., Kamae, T., Knödlseder, J., Kuss, M., Lande, J., Lionetto, A. M., Garde, M. Llena, Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., 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., Naumann-Godo, M., Norris, J. P., Nuss, E., Ohsugi, T., Okumura, A., Orlando, E., Ormes, J. F., Paneque, D., Panetta, J. H., Pesce-Rollins, M., Piron, F., Pivato, G., Porter, T. A., Prokhorov, D., Rainò, S., Rando, R., Razzano, M., Reimer, O., Roth, M., Sbarra, C., Scargle, J. D., Sgrò, C., Siskind, E. J., Snyder, A., Spinelli, P., Suson, D. J., Takahashi, H., Tanaka, T., Thayer, J. G., Thayer, J. B., Tibaldo, L., Tinivella, M., Torres, D. F., Tosti, G., Troja, E., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Waite, A. P., Winer, B. L., Wood, K. S., Yang, Z., and Zimmer, S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Nongalactic Astrophysics, High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: Dark matter particle annihilation or decay can produce monochromatic gamma-ray lines and contribute to the diffuse gamma-ray background. Flux upper limits are presented for gamma-ray spectral lines from 7 to 200 GeV and for the diffuse gamma-ray background from 4.8 GeV to 264 GeV obtained from two years of Fermi Large Area Telescope data integrated over most of the sky. We give cross section upper limits and decay lifetime lower limits for dark matter models that produce gamma-ray lines or contribute to the diffuse spectrum, including models proposed as explanations of the PAMELA and Fermi cosmic-ray data., Comment: Accepted for publication in Physical Review D
Published: 2012
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35. A 3D view of the outflow in the Orion Molecular Cloud 1 (OMC-1)

Author: Nissen, H. D., Cunningham, N. J., Gustafsson, M., Bally, J., Lemaire, J. -L., Favre, C., and Field, D.
Subjects: Astrophysics - Galaxy Astrophysics
Abstract: The fast outflow emerging from a region associated with massive star formation in the Orion Molecular Cloud 1 (OMC-1), located behind the Orion Nebula, appears to have been set in motion by an explosive event. Here we study the structure and dynamics of outflows in OMC-1. We combine radial velocity and proper motion data for near-IR emission of molecular hydrogen to obtain the first 3-dimensional (3D) structure of the OMC-1 outflow. Our work illustrates a new diagnostic tool for studies of star formation that will be exploited in the near future with the advent of high spatial resolution spectro-imaging in particular with data from the Atacama Large Millimeter Array (ALMA). We use published radial and proper motion velocities obtained from the shock-excited vibrational emission in the H2 v=1-0 S(1) line at 2.122 $\mu$m obtained with the GriF instrument on the Canada-France-Hawaii Telescope, the Apache Point Observatory, the Anglo-Australian Observatory and the Subaru Telescope. These data give the 3D velocity of ejecta yielding a 3D reconstruction of the outflows. This allows one to view the material from different vantage points in space giving considerable insight into the geometry. Our analysis indicates that the ejection occurred <720 years ago from a distorted ring-like structure of ~15" (6000 AU) in diameter centered on the proposed point of close encounter of the stars BN, source I and maybe also source n. We propose a simple model involving curvature of shock trajectories in magnetic fields through which the origin of the explosion and the centre defined by extrapolated proper motions of BN, I and n may be brought into spatial coincidence., Comment: Accepted for publication in Astronomy and Astrophysics (A&A), 12 pages, 9 figures
Published: 2012
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36. Anisotropies in the diffuse gamma-ray background measured by the Fermi LAT

Author: Ackermann, M., Ajello, M., Albert, A., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Bloom, E. D., Bonamente, E., Borgland, A. W., Brandt, T. J., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Buson, S., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Cecchi, C., Charles, E., Chekhtman, A., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Cuoco, A., Cutini, S., D'Ammando, F., de Palma, F., Dermer, C. D., Digel, S. W., Silva, E. do Couto e, Drell, P. S., Drlica-Wagner, A., Dubois, R., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Fortin, P., Fukazawa, Y., Fusco, P., Gargano, F., Gasparrini, D., Germani, S., Giglietto, N., Giroletti, M., Glanzman, T., Godfrey, G., Gomez-Vargas, G. A., Grégoire, T., Grenier, I. A., Grove, J. E., Guiriec, S., Gustafsson, M., Hadasch, D., Hayashida, M., Hayashi, K., Hou, X., Hughes, R. E., Jóhannesson, G., Johnson, A. S., Kamae, T., Knödlseder, J., Kuss, M., Lande, J., Latronico, L., Lemoine-Goumard, M., Linden, T., Lionetto, A. M., Garde, M. Llena, Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., Mazziotta, M. N., McEnery, J. E., Mitthumsiri, W., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Naumann-Godo, M., Norris, J. P., Nuss, E., Ohsugi, T., Okumura, A., Orienti, M., Orlando, E., Ormes, J. F., Paneque, D., Panetta, J. H., Parent, D., Pavlidou, V., Pesce-Rollins, M., Pierbattista, M., Piron, F., Pivato, G., Rainò, S., Rando, R., Reimer, A., Reimer, O., Roth, M., Sbarra, C., Schmitt, J., Sgrò, C., Siegal-Gaskins, J., Siskind, E. J., Spandre, G., Spinelli, P., Strong, A. W., Suson, D. J., Takahashi, H., Tanaka, T., Thayer, J. B., Tibaldo, L., Tinivella, M., Torres, D. F., Tosti, G., 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., Zimmer, S., and Komatsu, E.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Cosmology and Nongalactic Astrophysics, High Energy Physics - Phenomenology
Abstract: The contribution of unresolved sources to the diffuse gamma-ray background could induce anisotropies in this emission on small angular scales. We analyze the angular power spectrum of the diffuse emission measured by the Fermi LAT at Galactic latitudes |b| > 30 deg in four energy bins spanning 1 to 50 GeV. At multipoles \ell \ge 155, corresponding to angular scales \lesssim 2 deg, angular power above the photon noise level is detected at >99.99% CL in the 1-2 GeV, 2-5 GeV, and 5-10 GeV energy bins, and at >99% CL at 10-50 GeV. Within each energy bin the measured angular power takes approximately the same value at all multipoles \ell \ge 155, suggesting that it originates from the contribution of one or more unclustered source populations. The amplitude of the angular power normalized to the mean intensity in each energy bin is consistent with a constant value at all energies, C_P/^2 = 9.05 +/- 0.84 x 10^{-6} sr, while the energy dependence of C_P is consistent with the anisotropy arising from one or more source populations with power-law photon spectra with spectral index \Gamma_s = 2.40 +/- 0.07. We discuss the implications of the measured angular power for gamma-ray source populations that may provide a contribution to the diffuse gamma-ray background., Comment: 28 pages, 20 figures; accepted for publication in Phys. Rev. D; Contact authors: A. Cuoco, E. Komatsu, T. Linden, M. N. Mazziotta, J. Siegal-Gaskins, V. Vitale
Published: 2012
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37. Search for Dark Matter Satellites using the FERMI-LAT

Author: The Fermi LAT Collaboration, Ackermann, M., Albert, A., Baldini, L., Ballet, J., Barbiellini, G., Bastieri, D., Bechtol, K., Bellazzini, R., Blandford, R. D., Bloom, E. D., Bonamente, E., Borgland, A. W., Bottacini, E., Brandt, T. J., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Burnett, T. H., Caliandro, G. A., Cameron, R. A., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Charles, E., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Cutini, S., de Palma, F., Dermer, C. D., Digel, S. W., Silva, E. do Couto e, Drell, P. S., Drlica-Wagner, A., Essig, R., Falletti, L., Favuzzi, C., Fegan, S. J., Focke, W. B., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Guiriec, S., Gustafsson, M., Hadasch, D., Hayashida, M., Hou, X., Hughes, R. E., Johnson, R. P., Johnson, A. S., Kamae, T., Katagiri, H., Kataoka, J., Knodlseder, J., Kuss, M., Lande, J., Latronico, L., Lee, S. -H., Lionetto, A. M., Garde, M. Llena, Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., Mazziotta, M. N., McEnery, J. E., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Naumann-Godo, M., Norris, J. P., Nuss, E., Ohsugi, T., Okumura, A., Orlando, E., Ormes, J. F., Ozaki, M., Paneque, D., Pelassa, V., Pierbattista, M., Piron, F., Pivato, G., Porter, T. A., Raino, S., Rando, R., Razzano, M., Reimer, A., Reimer, O., Ritz, S., Sadrozinski, H. F. -W., Sehgal, N., Sgro, C., Siskind, E. J., Spinelli, P., Strigari, L., Suson, D. J., Tajima, H., Takahashi, H., Tanaka, T., Thayer, J. G., Thayer, J. B., Tibaldo, L., Tinivella, M., Torres, D. F., Troja, E., Uchiyama, Y., Usher, T. L., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Waite, A. P., Wang, P., Winer, B. L., Wood, K. S., Yang, Z., Zalewski, S., and Zimmer, S.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: Numerical simulations based on the Lambda-CDM model of cosmology predict a large number of as yet unobserved Galactic dark matter satellites. We report the results of a Large Area Telescope (LAT) search for these satellites via the gamma-ray emission expected from the annihilation of weakly interacting massive particle (WIMP) dark matter. Some dark matter satellites are expected to have hard gamma-ray spectra, finite angular extents, and a lack of counterparts at other wavelengths. We sought to identify LAT sources with these characteristics, focusing on gamma-ray spectra consistent with WIMP annihilation through the $b \bar b$ channel. We found no viable dark matter satellite candidates using one year of data, and we present a framework for interpreting this result in the context of numerical simulations to constrain the velocity-averaged annihilation cross section for a conventional 100 GeV WIMP annihilating through the $b \bar b$ channel., Comment: 29 pages, 5 figures, 3 tables; Accepted by ApJ; Contact authors: Alex Drlica-Wagner, Ping Wang, Louie Strigari, and Elliott Bloom
Published: 2012
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38. Measurement of separate cosmic-ray electron and positron spectra with the Fermi Large Area Telescope

Author: The Fermi LAT Collaboration, Ackermann, M., Ajello, M., Allafort, A., Atwood, W. B., Baldini, L., 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., Casandjian, J. M., Cecchi, C., Charles, E., Chekhtman, A., Cheung, C. C., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Cutini, S., de Angelis, A., de Palma, F., Dermer, C. D., Digel, S. W., Silva, E. do Couto e, Drell, P. S., Drlica-Wagner, A., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Focke, W. B., Fortin, P., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Germani, S., Giglietto, N., Giommi, P., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Grove, J. E., Guiriec, S., Gustafsson, M., Hadasch, D., Harding, A. K., Hayashida, M., Hughes, R. E., Jóhannesson, G., Johnson, A. S., Kamae, T., Katagiri, H., Kataoka, J., Knödlseder, J., Kuss, M., Lande, J., Latronico, L., Lemoine-Goumard, M., Garde, M. Llena, Longo, F., Loparco, F., Lovellette, M. N., Lubrano, P., Madejski, G. M., Mazziotta, M. N., McEnery, J. E., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Moiseev, A. A., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Nakamori, T., Nolan, P. L., Norris, J. P., Nuss, E., Ohno, M., Ohsugi, T., Okumura, A., Omodei, N., Ormes, E. Orlando J. F., Ozaki, M., Paneque, D., Parent, D., Pesce-Rollins, M., Pierbattista, 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., Roth, M., Sadrozinski, H. F. -W., Sbarra, C., Schalk, T. L., Sgrò, C., Siskind, E. J., Spandre, G., Spinelli, P., Strong, A. W., Takahashi, H., Takahashi, T., Tanaka, T., Thayer, J. G., Thayer, J. B., Tibaldo, L., Tinivella, M., Torres, D. F., Tosti, G., Troja, E., Uchiyama, Y., 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
Abstract: We measured separate cosmic-ray electron and positron spectra with the Fermi Large Area Telescope. Because the instrument does not have an onboard magnet, we distinguish the two species by exploiting the Earth's shadow, which is offset in opposite directions for opposite charges due to the Earth's magnetic field. We estimate and subtract the cosmic-ray proton background using two different methods that produce consistent results. We report the electron-only spectrum, the positron-only spectrum, and the positron fraction between 20 GeV and 200 GeV. We confirm that the fraction rises with energy in the 20-100 GeV range. The three new spectral points between 100 and 200 GeV are consistent with a fraction that is continuing to rise with energy., Comment: 5 figures, 1 table, revtex 4.1, updated to match PRL published version
Published: 2011
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39. Constraining Dark Matter Models from a Combined Analysis of Milky Way Satellites with the Fermi Large Area Telescope

Author: Collaboration, The Fermi-LAT, Ackermann, M., Ajello, M., Albert, A., 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., Bregeon, J., Brigida, M., Bruel, P., Buehler, R., Burnett, T. H., Buson, S., Caliandro, G. A., Cameron, R. A., Canadas, B., Caraveo, P. A., Casandjian, J. M., Cecchi, C., Charles, E., Chekhtman, A., Chiang, J., Ciprini, S., Claus, R., Cohen-Tanugi, J., Conrad, J., Cutini, S., de Angelis, A., de Palma, F., Dermer, C. D., Digel, S. W., Silva, E. do Couto e, Drell, P. S., Drlica-Wagner, A., Falletti, L., Favuzzi, C., Fegan, S. J., Ferrara, E. C., Fukazawa, Y., Funk, S., Fusco, P., Gargano, F., Gasparrini, D., Gehrels, N., Germani, S., Giglietto, N., Giordano, F., Giroletti, M., Glanzman, T., Godfrey, G., Grenier, I. A., Guiriec, S., Gustafsson, M., Hadasch, D., Hayashida, M., Hays, E., Hughes, R. E., Jeltema, T. E., Johannesson, G., Johnson, R. P., Johnson, A. S., Kamae, T., Katagiri, H., Kataoka, J., Knödlseder, J., Kuss, M., Lande, J., Latronico, L., Lionetto, A. M., Garde, M. Llena, Longo, F., Loparco, F., Lott, B., Lovellette, M. N., Lubrano, P., Madejski, G. M., Mazziotta, M. N., McEnery, J. E., Mehault, J., Michelson, P. F., Mitthumsiri, W., Mizuno, T., Monte, C., Monzani, M. E., Morselli, A., Moskalenko, I. V., Murgia, S., Naumann-Godo, M., Norris, J. P., Nuss, E., Ohsugi, T., Okumura, A., Omodei, N., Orlando, E., Ormes, J. F., Ozaki, M., Paneque, D., Parent, D., Pesce-Rollins, M., Pierbattista, M., Piron, F., Pivato, G., Porter, T. A., Profumo, S., Raino, S., Razzano, M., Reimer, A., Reimer, O., Ritz, S., Roth, M., Sadrozinski, H. F. -W., Sbarra, C., Scargle, J. D., Schalk, T. L., Sgro, C., Siskind, E. J., Spandre, G., Spinelli, P., Strigari, L., Suson, D. J., Tajima, H., Takahashi, H., Tanaka, T., Thayer, J. G., Thayer, J. B., Thompson, D. J., Tibaldo, L., Tinivella, M., Torres, D. F., Troja, E., Uchiyama, Y., Vandenbroucke, J., Vasileiou, V., Vianello, G., Vitale, V., Waite, A. P., Wang, P., Winer, B. L., Wood, K. S., Wood, M., Yang, Z., Zimmer, S., Kaplinghat, M., and Martinez, G. D.
Subjects: Astrophysics - High Energy Astrophysical Phenomena, High Energy Physics - Phenomenology
Abstract: Satellite galaxies of the Milky Way are among the most promising targets for dark matter searches in gamma rays. We present a search for dark matter consisting of weakly interacting massive particles, applying a joint likelihood analysis to 10 satellite galaxies with 24 months of data of the Fermi Large Area Telescope. No dark matter signal is detected. Including the uncertainty in the dark matter distribution, robust upper limits are placed on dark matter annihilation cross sections. The 95% confidence level upper limits range from about 1e-26 cm^3 s^-1 at 5 GeV to about 5e-23 cm^3 s^-1 at 1 TeV, depending on the dark matter annihilation final state. For the first time, using gamma rays, we are able to rule out models with the most generic cross section (~3e-26 cm^3 s^-1 for a purely s-wave cross section), without assuming additional boost factors., Comment: 6 pages, 2 figures; Contact authors: Johann Cohen-Tanugi, Jan Conrad, and Maja Llena Garde
Published: 2011
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40. Andreev tunneling in charge pumping with SINIS turnstiles

Author: Aref, T., Maisi, V. F., Gustafsson, M. V., Delsing, P., and Pekola, J. P.
Subjects: Condensed Matter - Mesoscale and Nanoscale Physics
Abstract: We present measurements on hybrid single-electron turnstiles with superconducting leads contacting a normal island (SINIS). We observe Andreev tunneling of electrons influencing the current plateau characteristics of the turnstiles under radio-frequency pumping. The data is well accounted for by numerical simulations. We verify the dependence of the Andreev tunneling rate on the turnstile's charging energy. Increasing the charging energy effectively suppresses the Andreev current., Comment: 6 pages, 4 figures, 1 table Published version with various improvements to figures and text
Published: 2011
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41. 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
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42. 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
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43. 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
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44. SEARCH FOR COSMIC-RAY-INDUCED GAMMA-RAY EMISSION IN GALAXY CLUSTERS

Author: Ackermann, M, Ajello, M, Albert, A, Allafort, A, Atwood, WB, Baldini, L, Ballet, J, Barbiellini, G, Bastieri, D, Bechtol, K, Bellazzini, R, Bloom, ED, Bonamente, E, Bottacini, E, Brandt, TJ, Bregeon, J, Brigida, M, Bruel, P, Buehler, R, Buson, S, Caliandro, GA, Cameron, RA, Caraveo, PA, Cavazzuti, E, Chaves, RCG, Chiang, J, Chiaro, G, Ciprini, S, Claus, R, Cohen-Tanugi, J, Conrad, J, D'Ammando, F, de Angelis, A, de Palma, F, Dermer, CD, Digel, SW, Drell, PS, Drlica-Wagner, A, Favuzzi, C, Franckowiak, A, Funk, S, Fusco, P, Gargano, F, Gasparrini, D, Germani, S, Giglietto, N, Giordano, F, Giroletti, M, Godfrey, G, Gomez-Vargas, GA, Grenier, IA, Guiriec, S, Gustafsson, M, Hadasch, D, Hayashida, M, Hewitt, J, Hughes, RE, Jeltema, TE, Jóhannesson, G, Johnson, AS, Kamae, T, Kataoka, J, Knödlseder, J, Kuss, M, Lande, J, Larsson, S, Latronico, L, Garde, M Llena, Longo, F, Loparco, F, Lovellette, MN, Lubrano, P, Mayer, M, Mazziotta, MN, McEnery, JE, Michelson, PF, Mitthumsiri, W, Mizuno, T, Monzani, ME, Morselli, A, Moskalenko, IV, Murgia, S, Nemmen, R, Nuss, E, Ohsugi, T, Orienti, M, Orlando, E, Ormes, JF, Perkins, JS, Pesce-Rollins, M, Piron, F, Pivato, G, Rainò, S, Rando, R, Razzano, M, Razzaque, S, Reimer, A, Reimer, O, Ruan, J, and Sánchez-Conde, M
Subjects: galaxies: clusters: intracluster medium, gamma rays: galaxies: clusters, astro-ph.HE, astro-ph.CO, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Physical Chemistry (incl. Structural), Astronomy & Astrophysics
Abstract: Current theories predict relativistic hadronic particle populations in clusters of galaxies in addition to the already observed relativistic leptons. In these scenarios hadronic interactions give rise to neutral pions which decay into γ rays that are potentially observable with the Large Area Telescope (LAT) on board the Fermi space telescope. We present a joint likelihood analysis searching for spatially extended γ-ray emission at the locations of 50 galaxy clusters in four years of Fermi-LAT data under the assumption of the universal cosmic-ray (CR) model proposed by Pinzke & Pfrommer. We find an excess at a significance of 2.7σ, which upon closer inspection, however, is correlated to individual excess emission toward three galaxy clusters: A400, A1367, and A3112. We discuss these cases in detail and conservatively attribute the emission to unmodeled background systems (for example, radio galaxies within the clusters).Through the combined analysis of 50 clusters, we exclude hadronic injection efficiencies in simple hadronic models above 21% and establish limits on the CR to thermal pressure ratio within the virial radius, R 200, to be below 1.25%-1.4% depending on the morphological classification. In addition, we derive new limits on the γ-ray flux from individual clusters in our sample. © 2014. The American Astronomical Society. All rights reserved.
Published: 2014

45. Inferred Cosmic-Ray Spectrum from Fermi Large Area Telescope γ-Ray Observations of Earth’s Limb

Author: Ackermann, M, Ajello, M, Albert, A, Allafort, A, Baldini, L, Barbiellini, G, Bastieri, D, Bechtol, K, Bellazzini, R, Blandford, RD, Bloom, ED, Bonamente, E, Bottacini, E, Bouvier, A, Brandt, TJ, Brigida, M, Bruel, P, Buehler, R, Buson, S, Caliandro, GA, Cameron, RA, Caraveo, PA, Cecchi, C, Charles, E, Chaves, RCG, Chekhtman, A, Chiang, J, Chiaro, G, Ciprini, S, Claus, R, Cohen-Tanugi, J, Conrad, J, Cutini, S, Dalton, M, D'Ammando, F, de Angelis, A, de Palma, F, Dermer, CD, Digel, SW, Di Venere, L, do Couto e Silva, E, Drell, PS, Drlica-Wagner, A, Favuzzi, C, Fegan, SJ, Ferrara, EC, Focke, WB, Franckowiak, A, Fukazawa, Y, Funk, S, Fusco, P, Gargano, F, Gasparrini, D, Germani, S, Giglietto, N, Giordano, F, Giroletti, M, Glanzman, T, Godfrey, G, Gomez-Vargas, GA, Grenier, IA, Grove, JE, Guiriec, S, Gustafsson, M, Hadasch, D, Hanabata, Y, Harding, AK, Hayashida, M, Hayashi, K, Hewitt, JW, Horan, D, Hou, X, Hughes, RE, Inoue, Y, Jackson, MS, Jogler, T, Jóhannesson, G, Johnson, AS, Kamae, T, Kawano, T, Knödlseder, J, Kuss, M, Lande, J, Larsson, S, Latronico, L, Longo, F, Loparco, F, Lovellette, MN, Lubrano, P, Mayer, M, Mazziotta, MN, McEnery, JE, Mehault, J, Michelson, PF, Mitthumsiri, W, Mizuno, T, Moiseev, AA, Monte, C, Monzani, ME, and Morselli, A
Subjects: Fermi LAT Collaboration, astro-ph.HE, Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract: Recent accurate measurements of cosmic-ray (CR) species by ATIC-2, CREAM, and PAMELA reveal an unexpected hardening in the proton and He spectra above a few hundred GeV, a gradual softening of the spectra just below a few hundred GeV, and a harder spectrum of He compared to that of protons. These newly discovered features may offer a clue to the origin of high-energy CRs. We use the Fermi Large Area Telescope observations of the γ-ray emission from Earth's limb for an indirect measurement of the local spectrum of CR protons in the energy range ∼90 GeV-6 TeV (derived from a photon energy range 15 GeV-1 TeV). Our analysis shows that single power law and broken power law spectra fit the data equally well and yield a proton spectrum with index 2.68±0.04 and 2.61±0.08 above ∼200 GeV, respectively.
Published: 2014

46. Dark matter constraints from observations of 25 Milky Way satellite galaxies with the Fermi Large Area Telescope

Author: Ackermann, M, Albert, A, Anderson, B, Baldini, L, Ballet, J, Barbiellini, G, Bastieri, D, Bechtol, K, Bellazzini, R, Bissaldi, E, Bloom, ED, Bonamente, E, Bouvier, A, Brandt, TJ, Bregeon, J, Brigida, M, Bruel, P, Buehler, R, Buson, S, Caliandro, GA, Cameron, RA, Caragiulo, M, Caraveo, PA, Cecchi, C, Charles, E, Chekhtman, A, Chiang, J, Ciprini, S, Claus, R, Cohen-Tanugi, J, Conrad, J, D’Ammando, F, de Angelis, A, Dermer, CD, Digel, SW, do Couto e Silva, E, Drell, PS, Drlica-Wagner, A, Essig, R, Favuzzi, C, Ferrara, EC, Franckowiak, A, Fukazawa, Y, Funk, S, Fusco, P, Gargano, F, Gasparrini, D, Giglietto, N, Giroletti, M, Godfrey, G, Gomez-Vargas, GA, Grenier, IA, Guiriec, S, Gustafsson, M, Hayashida, M, Hays, E, Hewitt, J, Hughes, RE, Jogler, T, Kamae, T, Knödlseder, J, Kocevski, D, Kuss, M, Larsson, S, Latronico, L, Garde, M Llena, Longo, F, Loparco, F, Lovellette, MN, Lubrano, P, Martinez, G, Mayer, M, Mazziotta, MN, Michelson, PF, Mitthumsiri, W, Mizuno, T, Moiseev, AA, Monzani, ME, Morselli, A, Moskalenko, IV, Murgia, S, Nemmen, R, Nuss, E, Ohsugi, T, Orlando, E, Ormes, JF, Perkins, JS, Piron, F, Pivato, G, Porter, TA, Rainò, S, Rando, R, Razzano, M, Razzaque, S, Reimer, A, Reimer, O, Ritz, S, Sánchez-Conde, M, Sehgal, N, and Sgrò, C
Subjects: astro-ph.HE, hep-ex, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Quantum Physics, Nuclear & Particles Physics
Abstract: The dwarf spheroidal satellite galaxies of the Milky Way are some of the most dark-matter-dominated objects known. Due to their proximity, high dark matter content, and lack of astrophysical backgrounds, dwarf spheroidal galaxies are widely considered to be among the most promising targets for the indirect detection of dark matter via γ rays. Here we report on γ-ray observations of 25 Milky Way dwarf spheroidal satellite galaxies based on 4 years of Fermi Large Area Telescope (LAT) data. None of the dwarf galaxies are significantly detected in γ rays, and we present γ-ray flux upper limits between 500 MeV and 500 GeV. We determine the dark matter content of 18 dwarf spheroidal galaxies from stellar kinematic data and combine LAT observations of 15 dwarf galaxies to constrain the dark matter annihilation cross section. We set some of the tightest constraints to date on the annihilation of dark matter particles with masses between 2 GeV and 10 TeV into prototypical standard model channels. We find these results to be robust against systematic uncertainties in the LAT instrument performance, diffuse γ-ray background modeling, and assumed dark matter density profile. © 2014 American Physical Society.
Published: 2014

47. Fermi-GBM Discovery of GRB 221009A: An Extraordinarily Bright GRB from Onset to Afterglow

Author: Lesage, S., primary, Veres, P., additional, Briggs, M. S., additional, Goldstein, A., additional, Kocevski, D., additional, Burns, E., additional, Wilson-Hodge, C. A., additional, Bhat, P. N., additional, Huppenkothen, D., additional, Fryer, C. L., additional, Hamburg, R., additional, Racusin, J., additional, Bissaldi, E., additional, Cleveland, W. H., additional, Dalessi, S., additional, Fletcher, C., additional, Giles, M. M., additional, Hristov, B. A., additional, Hui, C. M., additional, Mailyan, B., additional, Malacaria, C., additional, Poolakkil, S., additional, Roberts, O. J., additional, von Kienlin, A., additional, Wood, J., additional, Ajello, M., additional, Arimoto, M., additional, Baldini, L., additional, Ballet, J., additional, Baring, M. G., additional, Bastieri, D., additional, Gonzalez, J. Becerra, additional, Bellazzini, R., additional, Blandford, R. D., additional, Bonino, R., additional, Bruel, P., additional, Buson, S., additional, Cameron, R. A., additional, Caputo, R., additional, Caraveo, P. A., additional, Cavazzuti, E., additional, Chiaro, G., additional, Cibrario, N., additional, Ciprini, S., additional, Orestano, P. Cristarella, additional, Crnogorcevic, M., additional, Cuoco, A., additional, Cutini, S., additional, D’Ammando, F., additional, De Gaetano, S., additional, Di Lalla, N., additional, Di Venere, L., additional, Domínguez, A., additional, Fegan, S. J., additional, Ferrara, E. C., additional, Fleischhack, H., additional, Fukazawa, Y., additional, Funk, S., additional, Fusco, P., additional, Galanti, G., additional, Gammaldi, V., additional, Gargano, F., additional, Gasbarra, C., additional, Gasparrini, D., additional, Germani, S., additional, Giacchino, F., additional, Giglietto, N., additional, Gill, R., additional, Giroletti, M., additional, Granot, J., additional, Green, D., additional, Grenier, I. A., additional, Guiriec, S., additional, Gustafsson, M., additional, Hays, E., additional, Hewitt, J. W., additional, Horan, D., additional, Hou, X., additional, Kuss, M., additional, Latronico, L., additional, Laviron, A., additional, Lemoine-Goumard, M., additional, Li, J., additional, Liodakis, I., additional, Longo, F., additional, Loparco, F., additional, Lorusso, L., additional, Lovellette, M. N., additional, Lubrano, P., additional, Maldera, S., additional, Manfreda, A., additional, Martí-Devesa, G., additional, Mazziotta, M. N., additional, McEnery, J. E., additional, Mereu, I., additional, Meyer, M., additional, Michelson, P. F., additional, Mizuno, T., additional, Monzani, M. E., additional, Morselli, A., additional, Moskalenko, I. V., additional, Negro, M., additional, Nuss, E., additional, Omodei, N., additional, Orlando, E., additional, Ormes, J. F., additional, Paneque, D., additional, Panzarini, G., additional, Persic, M., additional, Pesce-Rollins, M., additional, Pillera, R., additional, Piron, F., additional, Poon, H., additional, Porter, T. A., additional, Principe, G., additional, Rainò, S., additional, Rando, R., additional, Rani, B., additional, Razzano, M., additional, Razzaque, S., additional, Reimer, A., additional, Reimer, O., additional, Ryde, F., additional, Sánchez-Conde, M., additional, Parkinson, P. M. Saz, additional, Scotton, L., additional, Serini, D., additional, Sgrò, C., additional, Sharma, V., additional, Siskind, E. J., additional, Spandre, G., additional, Spinelli, P., additional, Tajima, H., additional, Torres, D. F., additional, Valverde, J., additional, Venters, T., additional, Wadiasingh, Z., additional, Wood, K., additional, and Zaharijas, G., additional
Published: 2023
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48. Spatially resolved H2 emission from the disk around T Tau N

Author: Gustafsson, M., Labadie, L., Herbst, T. M., and Kasper, M.
Subjects: Astrophysics
Abstract: We report the detection of quiescent H2 emission in a spatially resolved ring-like structure within 100 AU of T Tau N. We present evidence to show that the emission most likely arises from shocks in the atmosphere of a nearly face-on disk around T Tau N. Using high spatial resolution 3D spectroscopic K-band data, we trace the spatial distribution of several H2 NIR rovibrational lines in the vicinity of T Tau N. We detect weak H2 emission from the v=1-0 S(0), S(1), Q(1) lines and the v=2-1 S(1) line in a ring-like structure around T Tau N between 0.1'' (~15 AU) and 0.7'' (~100AU) from the star. The v=1-0 S(0) and v=2-1 S(1) lines are detected only in the outer parts of the ring structure. Closer to the star, the strong continuum limits our sensitivity to these lines. The total flux of the v=1-0 S(1) line is 1.8 *10^{-14} ergs s^{-1}cm^{-2}, similar to previous measurements of H2 in circumstellar disks. The velocity of the H2 emitting gas around T Tau N is consistent with the rest velocity of the star, and the H2 does not seem to be part of a collimated outflow. Both shocks impinging on the surface of a disk and irradiation of a disk by UV-photons and X-rays from the central star are plausible candidates for the H2 excitation mechanism. However, irradiation should not create a large degree of excitation at radii larger than 20 AU. Most likely the H2 emission arises in the atmosphere of a flared disk with radius 85-100 AU and mass 0.005-0.5Msun, where the gas is excited by shocks created when a wide-angle wind impinges on the disk. The H2 emission could also originate from shock excitation in the cavity walls of an envelope, but this requires an unusually high velocity of the wide-angle wind from T Tau N., Comment: Accepted by A&A
Published: 2008
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49. Geotechnical engineering education and training in Sweden

Author: Sällfors, G.B., primary and Gustafsson, M., additional
Published: 2020
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50. SN 2003du: 480 days in the Life of a Normal Type Ia Supernova

Author: Stanishev, V., Goobar, A., Benetti, S., Kotak, R., Pignata, G., Navasardyan, H., Mazzali, P., Amanullah, R., Garavini, G., Nobili, S., Qiu, Y., Elias-Rosa, N., Ruiz-Lapuente, P., Mendez, J., Meikle, P., Patat, F., Pastorello, A., Altavilla, G., Gustafsson, M., Harutyunyan, A., Iijima, T., Jakobsson, P., Kichizhieva, M. V., Lundqvist, P., Mattila, S., Melinder, J., Pavlenko, E. P., Pavlyuk, N. N., Sollerman, J., Tsvetkov, D. Yu., Turatto, M., and Hillebrandt, W.
Subjects: Astrophysics
Abstract: An extensive set of optical and NIR photometry and low-resolution spectra the Type Ia supernova (SN Ia) 2003du was obtained using a number of facilities. The observations started 13 days before B-band maximum light and continued for 480 days with exceptionally good time sampling. The optical photometry was calibrated through the S-correction technique. The UBVRIJHK light curves and the color indices of SN 2003du closely resemble those of normal SNe Ia. SN 2003du reached a B-band maximum of 13.49 (+/-0.02) mag on JD2452766.38 (+/-0.5). We derive a B-band stretch parameter of 0.988 (+/-0.003), which corresponds to dM15=1.02 (+/-0.05), indicative of a SN Ia of standard luminosity. The reddening in the host galaxy was estimated by three methods, and was consistently found to be negligible. We estimate a distance modulus of 32.79 (+/-0.15) mag to the host galaxy, UGC 9391. The peak UVOIR bolometric luminosity of 1.35(+/-0.20) 10^43 erg/s and Arnett's rule implies that M(Ni56)=0.68 (+/-0.14)M_sun of Ni56 was synthesized during the explosion. Modeling of the UVOIR bolometric light curve also indicates M(Ni56) in the range 0.6-0.8 M_sun. The spectral evolution of SN 2003du at both optical and NIR wavelengths also closely resembles normal SNe Ia. In particular, the Si II ratio at maximum R(Si II)=0.22 (+/-0.02) and the time evolution of the blueshift velocities of the absorption line minima are typical. The pre-maximum spectra of SN 2003du showed conspicuous high-velocity features in the Ca II H&K doublet and infrared triplet, and possibly in Si II 6355, lines. We compare the time evolution of the profiles of these lines with other well-observed SNe Ia and we suggest that the peculiar pre-maximum evolution of Si II 6355 line in many SNe Ia is due to the presence of two blended absorption components., Comment: accepted for publication in A&A
Published: 2007
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