Astronomy and Astrophysics – Astrophysics
Scientific paper
2004-01-11
Astrophys.J.617:439-460,2004
Astronomy and Astrophysics
Astrophysics
38 pages, 10 figures; accepted for publication in ApJ (10 December 2004, v617)
Scientific paper
10.1086/425335
In this paper, we derive in a much detail the formula of count rates, in terms of the integral of time, of gamma-ray bursts in the framework of fireballs, where the Doppler effect of the expanding fireball surface is the key factor to be concerned. Effects arising from the limit of the time delay due to the limited regions of the emitting areas in the fireball surface and other factors are investigated. Our analysis shows that the formula of the count rate of fireballs can be expressed as a function of $\tau $ which is the observation time scale relative to the dynamical time scale of the fireball. The profile of light curves of fireballs depends only on the relative time scale, entirely independent of the real time scale and the real size of the objects. It displays in detail how a cutoff tail, or a turn over, feature (called a cutoff tail problem) in the decay phase of a light curve can be formed. This feature is a consequence of a hot spot in the fireball surface, moving towards the observer, and was observed in a few cases previously. By performing fits to the count rate light curves of six sample sources, we show how to obtain some physical parameters from the observed profile of the count rate of GRBs. In addition, the analysis reveals that the Doppler effect of fireballs could lead to a power law relationship between the $FWHM$ of pulses and energy, which were observed previously by many authors.
Cui Xiao-Hong
Qin Yi-Ping
Zhang Fu-Wen
Zhang Zhi-Bin
No associations
LandOfFree
Characteristics of profiles of gamma-ray burst pulses associated with the Doppler effect of fireballs does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Characteristics of profiles of gamma-ray burst pulses associated with the Doppler effect of fireballs, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Characteristics of profiles of gamma-ray burst pulses associated with the Doppler effect of fireballs will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-166679