Studies of intrinsic properties of gamma ray bursts detected by the HETE-II satellite

Analysis of HETE-II data is discussed with the aim of understanding the intrinsic properties of gamma-ray bursts (GRBs). A technique is developed that allows the simultaneous estimation of source and background counts during a burst with coded aperture instruments such as the Wide-field X-ray Monitor (WXM) on HETE-II. A closely related photon-by-photon statistical bootstrap analysis is then described that can be used to compute the non-Gaussian error distribution of GRB temporal statistics. This is applied to the T90 and To.45 duration measures. The distribution of T90 has been extensively studied since the availability of the BATSE gamma-ray burst catalogs and is widely believed to be log-normally distributed. It is shown that intrinsically, GRBs may in fact have a much narrower distribution, and the wide log-normal may primarily be due to measurement artifacts. Computation of the TO.45 parameter enables the inference of redshifts through the recently discovered Liso-Epk-TO.45 relation. This in turn allows the compilation of a flux-limited sample of bursts with redshifts that is free of the observational selection effects inherent in spectroscopic catalogs. This analysis is performed for 31 WXM bursts and redshift-corrected distributions of T90 and T0.45 are computed.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Physics.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2007

Author dc:creator

• Csatorday, Peter, 1973-

Advisor dc:contributor.advisor

• George R. Ricker and Saul Rappaport.

• Physics.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/39294

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/39294