论文标题
第四个BATSE目录中短GRB脉冲的特性:对喷射流出的结构和演变的影响
Properties of Short GRB Pulses in the Fourth BATSE Catalog: Implications for Structure and Evolution of the Jetted Outflows
论文作者
论文摘要
考虑到对单峰短伽马射线爆发(SGRB)和双峰SGRB之间脉冲时间特性的比较缺乏,我们使用BATSE时标(TTE)数据以5 ms分辨率研究了100个BATSE SGRBS样品的脉冲特性。 243个单个峰,双峰和三峰的SGRB适合其统计属性,例如脉搏不对称,振幅,高峰时间和脉搏宽度等。对于双峰峰的SGRB,根据两个相邻峰之间的重叠比率,我们首先定义了两个类型的型号,我们首先定义了这一型号,并找到了双重言论的人,并以双重至水平的速度来定位。脉冲类似于单峰的脉冲。我们研究了不同能带之间的全宽度依赖性对光子能量的一半(FWHM)的依赖性。有趣的是,发现单峰和双峰SGRB的FWHM和光子能量之间确实存在一个索引的幂律关系。更有趣的是,我们注意到有几个特殊的短爆发也存在带有正指数的幂律关系。鉴于脉冲的三个典型时间尺度,即角度扩散时间尺度,动态时间尺度和冷却时间尺度,我们提出,多样化的幂律索引与GRB脉冲的剖面相同,可以用作有效的探针,以诊断相关喷射的射流量的结构和进化。
Considering the shortage of comparative studies on pulse temporal characteristics between single-peaked short gamma-ray bursts (sGRBs) and double-peaked sGRBs, we examine the pulse properties of a sample of 100 BATSE sGRBs using the BATSE Time-Tagged Event (TTE) data with a 5-ms resolution. 243 individual pulses of the single-peaked, double-peaked and triple-peaked sGRBs are fitted to get their statistical properties such as the pulse asymmetry, amplitude, peak time, and pulse width, etc. For the double-peaked sGRBs, according to the overlapping ratio between two adjacent peaks, we first define two kinds of double-peaked sGRBs as M-loose and M-tight types and find that most of the first pulses are similar to the single-peaked ones. We study the dependence of the Full Width at Half Maximum (FWHM) on the photon energy among different energy bands. Interestingly, it is found that a power-law relation with an index of -0.4 does exist between the FWHM and the photon energy for the single- and double-peaked sGRBs. More interestingly, we notice that the power-law relation with a positive index also exist for several special short bursts. In view of the three typical timescales of pulses, namely the angular spreading timescale, the dynamic timescale, and the cooling timescale, we propose that the diverse power-law indexes together with the profile evolution of GRB pulse can be used as an effective probe to diagnose the structure and evolution of the relativistically jetted outflows.