%0 Journal Article
%T Bright Gamma-Ray Flares Observed in GRB 131108A
%+ Laboratoire Univers et Particules de Montpellier (LUPM)
%+ Laboratoire Leprince-Ringuet (LLR)
%+ Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112))
%+ Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG)
%A Ajello, M.
%A Arimoto, M.
%A Asano, K.
%A Axelsson, M.
%A Baldini, L.
%A Barbiellini, G.
%A Bastieri, D.
%A Bellazzini, R.
%A Berretta, A.
%A Bissaldi, E.
%A Blandford, R.D.
%A Bonino, R.
%A Bottacini, E.
%A Bregeon, J.
%A Bruel, P.
%A Buehler, R.
%A Buson, S.
%A Cameron, R.A.
%A Caputo, R.
%A Caraveo, P.A.
%A Cavazzuti, E.
%A Chen, S.
%A Chiaro, G.
%A Ciprini, S.
%A Costantin, D.
%A Cutini, S.
%A d'Ammando, F.
%A Torre Luque, P. de La
%A de Palma, F.
%A Lalla, N.Di
%A Venere, L.Di
%A Dirirsa, F.Fana
%A Fegan, S.J.
%A Franckowiak, A.
%A Fukazawa, Y.
%A Fusco, P.
%A Gargano, F.
%A Gasparrini, D.
%A Giglietto, N.
%A Giordano, F.
%A Giroletti, M.
%A Green, D.
%A Grenier, I.A.
%A Grondin, M.H.
%A Guiriec, S.
%A Hays, E.
%A Horan, D.
%A Jóhannesson, G.
%A Kocevski, D.
%A Kovacevic, M.
%A Kuss, M.
%A Larsson, S.
%A Latronico, L.
%A Li, J.
%A Liodakis, I.
%A Longo, F.
%A Loparco, F.
%A Lovellette, M.N.
%A Lubrano, P.
%A Maldera, S.
%A Manfreda, A.
%A Martí-Devesa, G.
%A Mazziotta, M.N.
%A Mcenery, J.E.
%A Mereu, I.
%A Michelson, P.F.
%A Mizuno, T.
%A Monzani, M.E.
%A Moretti, E.
%A Morselli, A.
%A Moskalenko, I.V.
%A Negro, M.
%A Nuss, E.
%A Ohno, M.
%A Omodei, N.
%A Orienti, M.
%A Orlando, E.
%A Palatiello, M.
%A Paliya, V.S.
%A Paneque, D.
%A Pei, Z.
%A Persic, M.
%A Pesce-Rollins, M.
%A Petrosian, V.
%A Piron, F.
%A Poon, H.
%A Porter, T.A.
%A Principe, G.
%A Racusin, J.L.
%A Rainò, S.
%A Rando, R.
%A Rani, B.
%A Razzano, M.
%A Reimer, A.
%A Reimer, O.
%A Serini, D.
%A Sgrò, C.
%A Siskind, E.J.
%A Spandre, G.
%A Spinelli, P.
%A Tajima, H.
%A Takagi, K.
%A Tak, Donggeun
%A Torres, D.F.
%A Valverde, J.
%A Wood, K.
%A Yamazaki, R.
%A Yassine, M.
%A Zhu, S.
%A Uhm, Z. Lucas
%A Zhang, Bing
%< avec comité de lecture
%J Astrophys.J.
%V 886
%N 2
%P L33
%8 2019
%D 2019
%Z 1911.04642
%R 10.3847/2041-8213/ab564f
%K gamma rays bursts
%K GRB131108A
%Z Physics [physics]/Astrophysics [astro-ph]Journal articles
%X GRB 131108A is a bright long gamma-ray burst (GRB) detected by the Large Area Telescope and the Gamma-ray Burst Monitor on board the Fermi Gamma-ray Space Telescope. Dedicated temporal and spectral analyses reveal three γ-ray flares dominating above 100 MeV, which are not directly related to the prompt emission in the Gamma-ray Burst Monitor band (10 keV–10 MeV). The high-energy light curve of GRB 131108A (100 MeV–10 GeV) shows an unusual evolution: a steep decay, followed by three flares with an underlying emission, and then a long-lasting decay phase. The detailed analysis of the γ-ray flares finds that the three flares are 6–20 times brighter than the underlying emission and are similar to each other. The fluence of each flare, (1.6 ∼ 2.0) × 10−6 erg cm−2, is comparable to that of emission during the steep decay phase, 1.7 × 10−6 erg cm−2. The total fluence from three γ-ray flares is 5.3 × 10−6 erg cm−2. The three γ-ray flares show properties similar to the usual X-ray flares that are sharp flux increases, occurring in ∼50% of afterglows, in some cases well after the prompt emission. Also, the temporal and spectral indices during the early steep decay phase and the decaying phase of each flare show the consistency with a relation of the curvature effect ( = 2 + ), which is the first observational evidence of the high-latitude emission in the GeV energy band.
%G English
%Z Fermi-LAT
%L hal-02409905
%U https://hal.science/hal-02409905
%~ IN2P3
%~ CEA
%~ INSU
%~ UNIV-PARIS7
%~ X
%~ CENBG
%~ LLR
%~ CNRS
%~ X-LLR
%~ X-DEP
%~ X-DEP-PHYS
%~ LUPM
%~ DSM-IRFU
%~ IRFU-AIM
%~ DSV
%~ USPC
%~ UNIV-PARIS-SACLAY
%~ X-SACLAY
%~ UNIV-MONTPELLIER
%~ CEA-DRF
%~ LUPM_EMA
%~ UNIV-PARIS
%~ UP-SCIENCES
%~ GS-PHYSIQUE
%~ UM-2015-2021