GRB without hard to soft evolution and their high energy emission
Abstract
Spectral properties of some GRB with presence of high energy component within RHESSI, HETE and SWIFT t90 intervals are discussed. In some cases the temporal profiles of GRB in low and high energy bands are similar but in some cases they are different and maxima are not coincide. We found the same type GRB in CGRO database too - for example, GRB930131. Moreover, for some GRB from CGRO and AVS-F database in which spectra contradict Band model high energy component are present the hard to soft spectral evolution is absent - for example, for GRB930506 (t90=22.144±0.091) Epeak on burst begin less than Epeak during other burst parts - Epeak(1-3s)=540±58 keV, Epeak(3-7s)=1064±38 keV, Epeak(7-23s)=850±32 keV. All GRB with such properties are long GRB for standatd BATSE and other classifications including taking in account burst hardness ones. We suppose that such type GRB consist a new subgroup of long GRB.
- Publication:
-
International Cosmic Ray Conference
- Pub Date:
- 2008
- Bibcode:
- 2008ICRC....3.1143A