Searching for differences in Swift's intermediate GRBs

Details Searching for differences in Swift's intermediate GRBs Searching for differences in Swift's intermediate GRBs

2010-06-23

arxiv.org/abs/1006.4469v2

Astron. Astrophys. 525 (2011), A109

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

Accepted for publication in Astronomy and Astrophysics. 16 pages, 17 figures, 5 tables

Scientific paper

10.1051/0004-6361/201015261

Gamma-ray bursts are usually classified through their high-energy emission into short-duration and long-duration bursts, which presumably reflect two different types of progenitors. However, it has been shown on statistical grounds that a third, intermediate population is needed in this classification scheme, although an extensive study of the properties of this class has so far not been done. The large amount of follow-up studies generated during the Swift era allows us to have a suficient sample to attempt a study of this third population through the properties of their prompt emission and their afterglows. Our study is focused on a sample of GRBs observed by Swift during its first four years of operation. The sample contains those bursts with measured redshift since this allows us to derive intrinsic properties. Intermediate bursts are less energetic and have dimmer afterglows than long GRBs, especially when considering the X-ray light curves, which are on average one order of magnitude fainter than long bursts. There is a less significant trend in the redshift distribution that places intermediate bursts closer than long bursts. Except for this, intermediate bursts show similar properties to long bursts. In particular, they follow the Epeak vs. Eiso correlation and have, on average, positive spectral lags with a distribution similar to that of long bursts. Like long GRBs, they normally have an associated supernova, although some intermediate bursts have shown no supernova component. This study shows that intermediate bursts are different from short bursts and, in spite of sharing many properties with long bursts, there are some differences between them as well. We suggest that the physical difference between intermediate and long bursts could be that for the first the ejecta are thin shells while for the latter they are thick shells.

Affiliated with

Also associated with

No associations

Rating

Searching for differences in Swift's intermediate GRBs 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 Searching for differences in Swift's intermediate GRBs, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Searching for differences in Swift's intermediate GRBs will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-277723