Sign on

SAO/NASA ADS Astronomy Abstract Service

· Find Similar Abstracts (with default settings below)
· Electronic On-line Article (HTML)
· Also-Read Articles (Reads History)
·
· Translate This Page
Title:
Gamma-ray bursts and their afterglows: Toward a unified model
Authors:
McMahon, Erin Malia
Affiliation:
AA(The University of Texas at Austin)
Publication:
Proquest Dissertations And Theses 2007. Section 0227, Part 0606 259 pages; [Ph.D. dissertation].United States -- Texas: The University of Texas at Austin; 2007. Publication Number: AAT 3297058. Source: DAI-B 69/02, Aug 2008
Publication Date:
00/2007
Origin:
UMI
Keywords:
Gamma-ray bursts, Afterglows, Synchrotron self-Compton
Bibliographic Code:
2007PhDT........33M

Abstract

Although much progress has been made in our understanding of gamma-ray bursts (GRBs) and their afterglows in the last few decades, some critical questions remain unanswered. One of these questions regards the form in which energy is transported from the explosion to the site at which the gamma-rays are produced -- i.e. is the energy carried in the kinetic energy of electrons and/or protons, or is much of it stored in a magnetic field? This dissertation documents a series of attempts to more clearly understand the nature of GRB outflows. First, we explore the possibility that the GRB is produced by an external shock, created when a baryonic outflow is decelerated by the surrounding medium. Next, emission from the external reverse shock is used to try to determine if the GRB ejecta is pair enriched. We then use data from several interesting, Swift -detected GRBs pin down the GRB emission radius, bulk Lorentz factor, magnetic field strength, and electron energy. We end by describing our nearly model independent method of modeling the GRB radiation as a combination of synchrotron and synchrotron self-Compton. We find that the GRB is likely to be produced by the synchrotron self-Compton radiation mechanism and predict that the accompanying prompt optical emission should be very high. If bright optical radiation during the GRB is not found, we think that this is good evidence that the acceleration of electrons is taking place repeatedly on a short timescale, effectively ruling out shock-based acceleration models.
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