An investigation of temporal characteristics of gamma-ray bursts observed with BATSE

Our knowledge of the gamma-ray burst distance scale has been revolutionized by recent observations made with the Burst and Transient Source Experiment (BATSE) onboard the Compton Gamma Ray Observatory. The combined observations of isotropy and inhomogeneity have geometrically eliminated the Galactic disk as a candidate distance scale. Two distances scales remain geometrically compatible with the data: an extended galactic halo (distance scale {dollar}sim{dollar} 100 kpc) or a population at distances so large that cosmological effects caused by an expanding spacetime become important. This dissertation uses BATSE data to investigate the temporal properties of gamma-ray bursts in an attempt to gain a better understanding of this phenomenon.; We present the first comprehensive study of gamma-ray bursts which exhibit precursor activity, as defined herein. Having systematically searched a data base of 995 bursts, we found that {dollar}sim{dollar}3% exhibit what we classify as precursor activity. We find no substantial evidence that the characteristics of the main emission are dependent upon the existence or nature of the precursor emission.; We describe in detail the methodology used to calculate {dollar}Tsb{lcub}90{rcub}{dollar} and {dollar}Tsb{lcub}50{rcub},{dollar} for bursts observed with BATSE. These two parameters characterize the durations of gamma-ray bursts. We use observed and simulated burst time profiles to examine the systematic effects associated with these measurements. The largest identified source of systematic error is that due to the difficulty of distinguishing source emission from background for certain profile shapes. These systematic effects, when present, work against the effects of cosmological time dilation.; We distinguish between parent and selected distributions of intrinsic and extrinsic {dollar}Tsb{lcub}90{rcub}{dollar}s, and discuss the instrumental dependence of the selected distributions of extrinsic {dollar}Tsb{lcub}90{rcub}{dollar}s.