GRB 110205A: ANATOMY OF A LONG GAMMA-RAY BURST

Journal Article · Tue Mar 20 00:00:00 EDT 2012 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/748/1/59· OSTI ID:22016141

Gendre, B; Stratta, G ^[1]; Atteia, J L; Klotz, A ^[2]; Boeer, M ^[3]; Colas, F; Vachier, F ^[4]; Kugel, F; Rinner, C ^[5]; Laas-Bourez, M ^[6]; Strajnic, J ^[7]

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1. ASDC, via Galileo Galilei, 00044 Frascati (Italy)
2. UPS-OMP, Universite de Toulouse, IRAP, Toulouse (France)
3. ARTEMIS (CNRS/UNS/OCA), Observatoire de la Cote d'Azur Boulevard de l'Observatoire, BP 4229, F-06304 Nice Cedex 4 (France)
4. IMCCE, Observatoire de Paris, 77 Avenue Denfert-Rochereau, 75014 Paris (France)
5. Observatory Chante-Perdrix, Dauban, 04150 Banon (France)
6. School of Physics/ICRAR, University of Western Australia, Crawley, WA 6009 (Australia)
7. Lycee de l'Arc, 84100 Orange, Academie d'Aix-Marseille (France)

The Swift burst GRB 110205A was a very bright burst visible in the Northern Hemisphere. GRB 110205A was intrinsically long and very energetic and it occurred in a low-density interstellar medium environment, leading to delayed afterglow emission and a clear temporal separation of the main emitting components: prompt emission, reverse shock, and forward shock. Our observations show several remarkable features of GRB 110205A: the detection of prompt optical emission strongly correlated with the Burst Alert Telescope light curve, with no temporal lag between the two; the absence of correlation of the X-ray emission compared to the optical and high-energy gamma-ray ones during the prompt phase; and a large optical re-brightening after the end of the prompt phase, that we interpret as a signature of the reverse shock. Beyond the pedagogical value offered by the excellent multi-wavelength coverage of a gamma-ray burst with temporally separated radiating components, we discuss several questions raised by our observations: the nature of the prompt optical emission and the spectral evolution of the prompt emission at high energies (from 0.5 keV to 150 keV); the origin of an X-ray flare at the beginning of the forward shock; and the modeling of the afterglow, including the reverse shock, in the framework of the classical fireball model.

• OSTI ID: 22016141
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 748; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
AFTERGLOW
COMPUTERIZED SIMULATION
COSMIC GAMMA BURSTS
FIREBALL MODEL
GALACTIC EVOLUTION
GAMMA RADIATION
NORTHERN HEMISPHERE
PHOTON EMISSION
STAR EVOLUTION
TELESCOPES
X RADIATION