2001/10/31 by Alicia M. Soderberg, Enrico Ramirez-Ruiz · 3 citations
Physics and Astronomy · #Component (thermodynamics) #Flash (photography) #Gamma-ray burst #Gamma-ray bursts and supernovae #Light curve #Optical depth #Pulsars and Gravitational Waves Research #Shock (circulatory) #Solar and Space Plasma Dynamics #astro-ph
paper · pdf · doi:10.1046/j.1365-8711.2002.05286.x
published as Mon.Not.Roy.Astron.Soc. 330 (2002) L24 · 6 pages, 4 figures; final version to be published in MNRAS
arxiv created 2002/02/01 · openalex publication_date 2002/02/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
GRB 990123 was a long, complex gamma-ray burst accompanied by an extremely bright optical flash. We find different constraints on the bulk Lorentz of this burst to be consistent with the speculation that the optical light is emission from the reverse shock component of the external shock. Motivated by this currently favoured idea, we compute the prompt reverse shock emission to be expected for bursts in which multiwavelength observations allow the physical parameters to be constrained. We find that for reasonable assumptions about the velocity of source expansion, a strong optical flash mV≈9 was expected from the reverse shocks, which were usually found to be mildly relativistic. The best observational prospects for detecting these prompt flashes are highlighted, along with the possible reasons for the absence of optical prompt detections in ongoing observations.