Modeling the Prompt Optical Emission of GRB 180325A: The Evolution of a Spike from the Optical to Gamma Rays

0547674 - ASÚ 2022 RIV US eng J - Článek v odborném periodiku
Becerra, R. L. - De Colle, F. - Cantó, J. - Araudo, Anabella … celkem 23 autorů
Modeling the Prompt Optical Emission of GRB 180325A: The Evolution of a Spike from the Optical to Gamma Rays.
Astrophysical Journal. Roč. 908, č. 1 (2021), č. článku 39. ISSN 0004-637X. E-ISSN 1538-4357
Grant CEP: GA ČR(CZ) GA20-19854S
Institucionální podpora: RVO:67985815
Klíčová slova: gamma-ray bursts * theoretical models * optical observation
Obor OECD: Astronomy (including astrophysics,space science)
Impakt faktor: 5.521, rok: 2021
Způsob publikování: Open access

The transition from prompt to afterglow emission is one of the most exciting and least understood phases in gamma-ray bursts (GRBs). Correlations among optical, X-ray, and gamma-ray emission in GRBs have been explored, to attempt to answer whether the earliest optical emission comes from internal and/or external shocks. We present optical photometric observations of GRB 180325A collected with the TAROT and RATIR ground-based telescopes. These observations show two strong optical flashes with separate peaks at ∼50 and ∼120 s, followed by a temporally extended optical emission. We also present X-rays and gamma-ray observations of GRB 180325A, detected by the Burst Alert Telescope and X-ray Telescope, on the Neil Gehrels Swift observatory, which both observed a narrow flash at ∼80 s. We show that the prompt gamma-ray and X-ray early emission shares similar temporal and spectral features consistent with internal dissipation within the relativistic outflow (e.g., by internal shocks or magnetic reconnection), while the early optical flashes are likely generated by the reverse shock that decelerates the ejecta as it sweeps up the external medium.
Trvalý link: http://hdl.handle.net/11104/0323865