Properties of Gamma-Ray Burst Time Profiles Using Pulse Decomposition Analysis
Properties of Gamma-Ray Burst Time Profiles Using Pulse Decomposition Analysis
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DOI：
10.1086/317364
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发表时间：
2000-02
期刊：
影响因子：
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通讯作者：
A. Lee;E. Bloom;V. Petrosian
中科院分区：
文献类型：
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作者：
A. Lee;E. Bloom;V. Petrosian
许多伽玛射线暴的时间分布由不同的脉冲组成，这提供了使用相对较小的脉冲形状参数来表征这些暴的时间结构的可能性。这种脉冲分解分析之前已经使用来自BATSE的分箱数据对明亮的长脉冲串的小样本进行了分析，该数据有几种数据类型，并且使用BATSE时间标记事件（TTE）数据类型对短脉冲串的样本进行了分析。我们已经开发了一个交互式脉冲拟合程序，使用诺里斯等人的现象脉冲模型和最大似然拟合例程。我们已经使用这个程序来分析的时间溢出（TTS）数据的所有突发观测到的BATSE通过触发数2000，在所有的能源渠道，TTS数据是可用的。这表示在一个或多个能量通道中分析的总共211个不同的突发。我们提出了统计信息的属性，包括这些突发脉冲，包括在不同的能量通道和脉冲特性的演变过程中的突发脉冲特性之间的关系。我们进行模拟，以确定我们的程序可能引入的偏差。我们发现，脉冲往往有较短的上升时间比衰减时间，往往是更窄，峰值更早，在更高的能量。我们还发现，脉冲亮度，脉冲宽度和脉冲硬度比不单调地演变内突发，但脉冲上升时间的比率衰减时间内突发往往随时间的推移而减少。
The time profiles of many gamma-ray bursts consist of distinct pulses, which offers the possibility of characterizing the temporal structure of these bursts using a relatively small set of pulse shape parameters. This pulse decomposition analysis has previously been performed on a small sample of bright, long bursts using binned data from BATSE, which comes in several data types, and on a sample of short bursts using the BATSE time-tagged event (TTE) data type. We have developed an interactive pulse-fitting program using the phenomenological pulse model of Norris et al. and a maximum-likelihood fitting routine. We have used this program to analyze the time-to-spill (TTS) data for all bursts observed by BATSE up through trigger number 2000, in all energy channels for which TTS data is available. This represents a total of 211 distinct bursts analyzed in one or more energy channels. We present statistical information on the attributes of pulses comprising these bursts, including relations between pulse characteristics in different energy channels and the evolution of pulse characteristics through the course of a burst. We carry out simulations to determine the biases that our procedures may introduce. We find that pulses tend to have shorter rise times than decay times, and tend to be narrower and peak earlier at higher energies. We also find that pulse brightness, pulse width, and pulse hardness ratios do not evolve monotonically within bursts, but that the ratios of pulse rise times to decay times tend to decrease with time within bursts.