2007/08/31 by Kohta Murase, Kunihito Ioka · 5 citations
Engineering · Physics and Astronomy · #Astronomy and Astrophysical Research #CCD and CMOS Imaging Sensors #Closure (psychology) #Cutoff #Energy (signal processing) #Gamma-ray burst #Gamma-ray bursts and supernovae #Line (geometry) #Photosphere #Satellite #Telescope #astro-ph
paper · pdf · doi:10.1086/527667
published as Astrophys.J. 676 (2008) 1123 · 7 pages, 4 figures, accepted for publication in ApJ, with extended discussions. Conclusions unchanged
arxiv created 2007/12/03 · openalex publication_date 2008/03/27 · arxiv updated 2015/04/23 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present recipes to diagnose the fireball of gamma-ray bursts (GRBs) by combining observations of e ± pair signatures (the pair annihilation line and the cutoff energy due to the pair creation process). Our recipes are largely model-independent and extract information even from the nondetection of either pair signature. We evaluate physical quantities such as the Lorentz factor, optical depth, and pair-to-baryon ratio only from the observable quantities. In particular, we can test whether the prompt emission of GRBs comes from the pair/baryonic photosphere or not. The future Gamma-Ray Large Area Space Telescope ( GLAST ) satellite will provide us with good chances to use our recipes via either detection or nondetection of pair signatures.