Emission processes in gamma-ray bursts
| dc.creator | Ghisellini, Gabriele | |
| dc.date | 1999-07-27 | |
| dc.date.accessioned | 2026-07-07T02:32:39Z | |
| dc.date.available | 2026-07-07T02:32:39Z | |
| dc.description | Recent results of the hectic research activity about gamma-ray bursts will be reviewed, with emphasis about the emission processes at the origin of the observed gamma-rays. The conventional synchrotron shock scenario is found to have problems, due to the very short cooling times of the emitting electrons, which implies a predicted spectrum F(nu) proportional to nu^(-1/2), much steeper than what is observed. It is therefore compelling to look for alternative emission processes, such as quasi-thermal Comptonization, implying the presence of mildly or sub-relativistic electrons, producing, through multiple Compton scatterings, a spectrum proportional to nu^0 ending with a Wien peak where photons and electron energies balance. The afterglow light, instead, can be indeed due to synchrotron radiation, and a confirmation of this is the recently detected optical linear polarization of the afterglow of GRB 990510. Some consequences of this discovery will be outlined. A quantum leap in our understanding of the physics of gamma-ray bursts is expected to come with SWIFT, a NASA-MIDEX dedicated satellite. | |
| dc.description | 10 pages, 3 figures, invited paper at the XLIII meeting of the Italian Astronomical Society: "Revolutions in Astronomy" (May 1999) | |
| dc.identifier | https://arxiv.org/abs/astro-ph/9907376 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/9907376 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/14537 | |
| dc.subject | Astrophysics | |
| dc.title | Emission processes in gamma-ray bursts | |
| dc.type | text |