Afterglow Radiation from Gamma Ray Bursts

Desmond, Hugh ; /SLAC, /Leuven U.

Stanford Linear Accelerator Center

关键词: Decay;    Astrophysics,Astro;    Mathematical Models;    71 Classical And Quantum Mechanics, General Physics;    Afterglow;   

DOI  :  10.2172/890774
RP-ID  :  SLAC-TN-06-013
RP-ID  :  AC02-76SF00515
RP-ID  :  890774

美国|英语

来源: UNT Digital Library

【 摘 要 】

Gamma-ray bursts (GRB) are huge fluxes of gamma rays that appear randomly in the sky about once a day. It is now commonly accepted that GRBs are caused by a stellar object shooting off a powerful plasma jet along its rotation axis. After the initial outburst of gamma rays, a lower intensity radiation remains, called the afterglow. Using the data from a hydrodynamical numerical simulation that models the dynamics of the jet, we calculated the expected light curve of the afterglow radiation that would be observed on earth. We calculated the light curve and spectrum and compared them to the light curves and spectra predicted by two analytical models of the expansion of the jet (which are based on the Blandford and McKee solution of a relativistic isotropic expansion; see Sari's model [1] and Granot's model [2]). We found that the light curve did not decay as fast as predicted by Sari; the predictions by Granot were largely corroborated. Some results, however, did not match Granot's predictions, and more research is needed to explain these discrepancies.