The Intrinsic Statistical Properties Of Gamma-Ray Burst Prompt Emission

Gamma-ray bursts(GRBs)are the most powerful explosion since the Big Bang.They have been one of the hot topics in astronomy and physics since they were discovered in the 1960s.In recent years,with the launch of gamma-ray observation satellites and the detection of ground multi-band telescopes,researchers have made a series of important results.However,some basic problems of GRBs,such as the central engine and radiation mechanism,are still not known.With the accumulation of observational data,the intrinsic statistical investigations of GRBs will play an important role in solving these problems.This paper focuses on the statistical study of the latest GRBs prompt emission observation data,and explore about the intrinsic statistical properties of GRBs prompt emission.The results will be used to constrain the physical models of GRBs.This paper is divided into five chapters.The first chapter gives a brief overview of the research of GRBs.The second chapter introduces the statistical relations in GRBs prompt emission.The third and forth chapters are our works on the long GRBs and short GRBs,respectively.The final chapter is the conclusion.GRBs move at an extreme relativistic velocity.Due to the limitation of observation,it is difficult to obtain the initial lorentz factors of GRBs.We estimate the initial lorentz factor of 225 long GRBs by using a tight three-parameter correlation Liso-Ep-Г0,which was found in the long GRBs,and then study the intrinsic statistical properties in the co-moving frame.The results show that the distributions of the isotropic energy,luminosity,peak energy and duration of GRBs are basically lognormal in different frames and more concentrated in the co-moving frame.This suggests that the intrinsic properties of long GRBs are not very different.We further verify the spectrum-energy relations and Liso(Eiso)-Г0 relations.We found that the corresponding correlations still exist in the co-moving frame,but with large dispersions.This indicates that the spectrum-energy relations and the initial lorentz factor-energy relations do exist for long GRBs.But these relations are affected significantly by the redshift and lorentz factor.Short GRBs are thought to have different physical origins from long GRBs.We study the spectrum-energy relation of short GRBs by using 26 short GRBs with known redshift and well measured spectrum.The results further confirm there are the similar spectrum-energy relations between short and long GRBs,which indicates that both short and long GRBs may have the same emission process.We also find that there is a weak anti-correlation between isotropic luminosity,peak energy and duration.This suggests that the shorter the duration of GRB is,the brighter and more energetic it is.However,these results need to be further confirmed.