A Search for Short Duration Very High Energy Emission from Gamma-Ray Bursts Energy, Emission, Duration, Short, Search

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A Search for Short Duration Very High Energy Emission from Gamma-Ray Bursts

by:?David Carl Noyes
en?|?Digital Repository at the University of Maryland University of Maryland (College Park, Md.)

R20090520T?   


  
Title:???? A Search for Short Duration Very High Energy Emission from Gamma-Ray Bursts
Author:???? Noyes, David Carl
Department/Program:???? Physics
Type:???? Dissertation
Sponsors:???? Digital Repository at the University of Maryland
University of Maryland (College Park, Md.)
Keywords:???? Physics, Astronomy and Astrophysics (0606)
Gamma-Ray Bursts, GRB, Very High Energy, VHE
?  
Abstract:
Milagro is a water-Cherenkov detector capable of observing air showers produced by gamma rays with primary energies of approximately 100 GeV and higher. The wide field of view (" 2 sr) and high duty cycle (>90%) of Milagro make it ideal for searching for transient emission from gamma-ray bursts (GRBs). The median energy of photons detected by Milagro is a few TeV, but the effective area is still relatively large at a few hundred GeV ("50 m^2 at 100 GeV). This results in a gamma-ray fluence sensitivity comparable to previous satellite detectors at keV energies. Measurements have been made of GRB spectra up to a few tens of GeV with no sign of a cutoff, however much is still unknown about the nature and existence of this Very High Energy (VHE) component. Additionally, gamma/gamma absorption from infrared background photons or from the optically thick region of the burst source complicate observations of this VHE component  
Contents
A Search For Short Duration Very High Energyemission From Gamma-ray Bursts
Abstract
Acknowledgements
Table Of Contents
List Of Tables
List Of Figures
Chapter 1 Gamma-ray Bursts
???? 1.1 Introduction
???? 1.2 Experimental History
???? 1.3 GRB Theory
???? 1.4 VHE Emission from GRBs
Chapter 2 Milagro: A Vhe Gamma-ray Observatory
???? 2.1 Introduction
???? 2.2 Cosmic Rays, Extensive Air Showers, and Cherenkov Radiation
???? 2.3 Detector Description
???? 2.4 The Electronics and DAQ System
???? 2.5 Calibration
???? 2.6 Event Reconstruction
???? 2.7 Optimal Bin Size
???? 2.8 Background Rejection
Chapter 3 The Gamma-Ray Burst Search
???? 3.1 Introduction
???? 3.2 Search Description
???? 3.3 Search Results
???? Chapter 4
Chapter 4 Sensitivity To Grbs And Results
???? 4.1 Introduction
???? 4.2 Definitions
???? 4.3 Calculating the Number of Photons from a Source: The E ective Area
???? 4.4 Modi cations to the Spectrum
???? 4.5 Model Independent Sensitivity Calculations
???? 4.6 Limits on GRB Properties
Chapter 5 Conclusions
???? 5.1 Summary
???? 5.2 Future Directions
Bibliography                   下载链接:source: http://link.aip.org/link/?APCPCS/836/620/1

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