Panaitescu 2007 GeV emission from Gamma-Ray Burst afterglows

主要内容:
Considering 4 mechanism for High energy emission for GLAST:
1. curvature effect of prompt emission;
2. spectral extension of X-ray (-p/2);
3. SSC of normal afterglow;
4. Bulk-scattering of GRB emission.

精彩摘抄:


文章信息:
arXiv:0712.1536 [ps, pdf, other]

Title: GeV emission from Gamma-Ray Burst afterglows

Authors: A. Panaitescu

Comments: 7 pages (too long to be reviewed in only 6 weeks)

Subjects: Astrophysics (astro-ph)

We calculate the GeV afterglow emission expected from a few mechanisms related to GRBs and their afterglows. Given the brightness of the early X-ray afterglow emission measured by Swift/XRT, GLAST/LAT should detect the self-Compton emission from the forward-shock driven by the GRB ejecta into the circumburst medium. Novel features discovered by Swift in X-ray afterglows (plateaus and chromatic light-curve breaks) indicate the existence of a pair-enriched, relativistic outflow located behind the forward shock. Bulk and inverse-Compton upscattering of the prompt GRB emission by such outflows provide another source of GeV afterglow emission detectable by LAT. The large-angle burst emission and synchrotron forward-shock emission are, most likely, too dim at high photon energy to be observed by LAT. The spectral slope of the high-energy afterglow emission and its decay rate (if it can be measured) allow the identification of the mechanism producing the GeV transient emission following GRBs