Sign on

SAO/NASA ADS arXiv e-prints Abstract Service

· Find Similar Abstracts (with default settings below)
· arXiv e-print (arXiv:0910.2456)
· References in the Article
· Citations to the Article (2) (Citation History)
· Refereed Citations to the Article
· Also-Read Articles (Reads History)
·
· Translate This Page
Title:
Threshold for Extended Emission in Short Gamma-Ray Bursts
Authors:
Norris, Jay P.; Gehrels, Neil; Scargle, Jeffrey D.
Publication:
eprint arXiv:0910.2456
Publication Date:
10/2009
Origin:
ARXIV
Keywords:
Astrophysics - High Energy Astrophysical Phenomena
Comment:
20 pages, 7 figures; submitted to Astrophysical Journal
Bibliographic Code:
2009arXiv0910.2456N

Abstract

The initial pulse complex (IPC) in short gamma-ray bursts is sometimes accompanied by a softer, low-intensity extended emission (EE) component. In cases where such a component is not observed, it is not clear if it is present but below the detection threshold. Using Bayesian Block (BB) methods, we measure the EE component and show that it is present in one quarter of a Swift/BAT sample of 47 short bursts, as was found for the Compton/BATSE sample. We simulate bursts with EE to calibrate the BAT threshold for EE detection and show that this component would have been detected in ~ half of BAT short bursts if it were present, to intensities ~ 10^-2 counts cm^-2 s^-1, a factor of five lower than actually observed in short bursts. In the BAT sample the ratio of average EE intensity to IPC peak intensity, Rint, ranges over a factor of 25, Rint ~ 3 x 10^-3 to 8 x 10^-2. In comparison, for the average of the 35 bursts without an EE component, the 2-sigma upper limit is Rint < 5 x 10^-4. These results suggest that a physical threshold effect operates near Rint ~ few x 10^-3, below which the EE component is not manifest.
Bibtex entry for this abstract   Preferred format for this abstract (see Preferences)
   

Find Similar Abstracts:

Use: Authors
Title
Keywords (in text query field)
Abstract Text
Return: Query Results Return    items starting with number
Query Form
Database: Astronomy
Physics
arXiv e-prints