主要内容:
提出目前费米暴的特征和对应的问题。
会议论文
精彩摘抄:
文章信息:
- · arXiv e-print (arXiv:1003.2452)
- · References in the Article
- · Citations to the Article (3) (Citation History)
- · Refereed Citations to the Article
- · Also-Read Articles (Reads History)
- ·
- · Translate This Page
| Title: |
| Highlights from Fermi GRB observations |
| Authors: |
| Granot, Jonathan; for the Fermi LAT Collaboration; the GBM Collaboration |
| Publication: |
| eprint arXiv:1003.2452 |
| Publication Date: |
| 03/2010 |
| Origin: |
| ARXIV |
| Keywords: |
| Astrophysics - High Energy Astrophysical Phenomena |
| Comment: |
| 13 pages, 3 figures, 2 tables; to be published in the Proceedings of "The Shocking Universe - Gamma-Ray Bursts and High Energy Shock phenomena", Venice (Italy), September 14-18, 2009 (based on an invited talk there, but updated to include results up to the end of January 2010) |
| Bibliographic Code: |
| 2010arXiv1003.2452G |
Abstract
The Fermi Gamma-Ray Space Telescope has more than doubled the number of Gamma-Ray Bursts (GRBs) detected above 100 MeV within its first year of operation. Thanks to the very wide energy range covered by Fermi's Gamma-ray Burst Monitor (GBM; 8 keV to 40 MeV) and Large Area Telescope (LAT; 25 MeV to >300 GeV) it has measured the prompt GRB emission spectrum over an unprecedentedly large energy range (from ~8 keV to ~30 GeV). Here I briefly outline some highlights from Fermi GRB observations during its first ~1.5 yr of operation, focusing on the prompt emission phase. Interesting new observations are discussed along with some of their possible implications, including: (i) What can we learn from the Fermi-LAT GRB detection rate, (ii) A limit on the variation of the speed of light with photon energy (for the first time beyond the Planck scale for a linear energy dependence from direct time of arrival measurements), (iii) Lower-limits on the bulk Lorentz factor of the GRB outflow (of ~1000 for the brightest Fermi LAT GRBs), (iv) The detection (or in other cases, lack thereof) of a distinct spectral component at high (and sometimes also at low) energies, and possible implications for the prompt GRB emission mechanism, (v) The later onset (and longer duration) of the high-energy emission (>100 MeV), compared to the low-energy (< ~1 MeV) emission, that is seen in most Fermi-LAT GRBs.
没有评论:
发表评论