Spectral lags in different episodes of gamma-ray bursts  

作　　者：JIA LanWei YI TingFeng LIANG EnWei 

机构地区：[1]Department of Physics,Guangzhou University [2]Department of Physics,Yunnan Normal University [3]Department of Physics and GXU-NAOC Center for Astrophysics and Space Sciences,Guangxi University

出　　处：《Science China(Physics,Mechanics & Astronomy)》2013年第8期1437-1442,共6页中国科学：物理学、力学、天文学（英文版）

基　　金：the National Basic Research Program of China (Grant No. 2009CB824800);the National Natural Science Foundation of China (Grant Nos. 11025313 and 11203008);the Special Foundation for Distinguished Expert Program of Guangxi;the Guangxi Natural Science Foundation (Grant No. 2013GXNSFFA019001) and Contract No.2011-135

摘　　要：A systematical analysis of the spectral lags in different episodes within a gamma-ray burst (GRB) for the BATSE GRB sample is given. The identified episodes are usually a single pulse with mixing of small fluctuations. The spectral lags were calculated for lightcurves in the 25-55 keV and 110-320 keV bands. No universal spectral lag evolution feature in different episodes within a GRB were found for most GRBs. Among 362 bright GRBs that have at least three well-identified episodes, 19 of them show long-to-short lag and 19 of them show short-to-long lag in successive episodes. The other 324 GRBs have no clear evolution trend. Defining the specified lag with the ratio of the spectral lag to the episode duration in 110-320 keV band, no prominent case of specified lag was found showing clear evolution features. The results suggest that the observed spectral lag may contribute to the dynamics and/or the radiation physics of a given emission episode.A systematical analysis of the spectral lags in different episodes within a gamma-ray burst （GRB） for the BATSE GRB sample is given. The identified episodes are usually a single pulse with mixing of small fluctuations. The spectral lags were calculated for lightcurves in the 25-55 keV and 110-320 keV bands. No universal spectral lag evolution feature in different episodes within a GRB were found for most GRBs. Among 362 bright GRBs that have at least three well-identified episodes, 19 of them show long-to-short lag and 19 of them show short-to-long lag in successive episodes. The other 324 GRBs have no clear evolution trend. Defining the specified lag with the ratio of the spectral lag to the episode duration in 110-320 keV band, no prominent case of specified lag was found showing clear evolution features. The results suggest that the observed spectral lag may contribute to the dynamics and/or the radiation physics of a given emission episode.

关 键 词：γ-pray  gamma-rays bursts  time series analysis  statistics 

分 类 号：O571.321[理学—粒子物理与原子核物理]