| タイトル | GRB110721A: An Extreme Peak Energy and Signatures of the Photosphere |
| 本文（外部サイト） | http://hdl.handle.net/2060/20130013642 |
| 著者（英） | Ferrara, E. C.; Chaves, R. C. G.; Cecchi, C.; Brigida, M.; Chekhtman, A.; Guiriec, S.; Axelsson, M.; Wilson-Hodge, C.; Caliandro, G. A.; Cutini, S.; Bellazzini, R.; Buehler, R.; Baldini, L.; McEnery, J. E.; Gehrels, N.; Claus, R.; Bruel, P.; Fishman, G.; Barbiellini, G.; Caraveo, P. A.; Conrad, J.; Baring, M. G.; Bregeon, J.; Cameron, R. A.; Chiang, J. |
| 著者所属（英） | NASA Goddard Space Flight Center |
| 発行日 | 2012-10-01 |
| 言語 | eng |
| 内容記述 | GRB110721A was observed by the Fermi Gamma-ray Space Telescope using its two instruments, the Large Area Telescope (LAT) and the Gamma-ray Burst Monitor (GBM). The burst consisted of one major emission episode which lasted for approximately 24.5 s (in the GBM) and had a peak flux of (5.7 +/- 0.2) 10(exp -5) erg s(exp -1) cm(exp -2). The time-resolved emission spectrum is best modeled with a combination of a Band function and a blackbody spectrum. The peak energy of the Band component was initially 15 +/- 2 MeV, which is the highest value ever detected in a GRB. This measurement was made possible by combining GBM/BGO data with LAT Low Energy events to achieve continuous 10-100 MeV coverage. The peak energy later decreased as a power law in time with an index of -1.89 +/- 0.10. The temperature of the blackbody component also decreased, starting from approximately 80 keV, and the decay showed a significant break after approximately 2s. The spectrum provides strong constraints on the standard synchrotron model, indicating that alternative mechanisms may give rise to the emission at these energies. |
| NASA分類 | Astrophysics |
| レポートNO | GSFC-E-DAA-TN9742
GSFC-E-DAA-TN8389 |
| 権利 | Copyright, Distribution as joint owner in the copyright |
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