Galli 2007 外激波的逆康普顿散射

主要内容:
认为可对高能的Flare和余辉的高能负责。

精彩摘抄:


文章信息:
arXiv:0705.4061 [ps, pdf, other] : Title: High energy afterglows and flares from Gamma-Ray Burst by Inverse Compton emission
Authors: A. Galli (1,2,3), L. Piro (1) ((1) IASF-Roma/INAF, (2) Univerisita' di Roma "La Sapienza", (3) INFN-Trieste)
Comments: 15 pages, 20 figures, submitted to Astronomy and Astrophysics

We perform a detailed study of Inverse Compton (IC) emission for a fireball undergoing External Shock (ES) in either a uniform or a wind-like interstellar medium, and assess the relative importance of IC and synchrotron emission. We determine the primary model parameters driving the IC to synchrotron emission ratio in the case of a short duration central engine. We then investigate the case of ES by a long duration central engine, a model that can account for some of the flares observed in Gamma-ray Bursts X-ray light curves at late times. We present model predictions, in particular in terms of GeV vs X-ray behaviour, and compare them with other models proposed to explain the origin of flares. We find that if most of the emission occurs when the fireball is in the fast cooling regime then a substantial GeV emission is expected. In particular we are able to account for the delayed emission observed in GRB940217. In the case of ES by a long duration central engine we find that IC scattering of X-ray flare photons can produce high energy flares in the GeV band, that can be detected by the Large Area Telescope aboard GLAST. Observations by Swift and GLAST will thus help in discriminating between these models.