主要内容:
他们利用SFC方法，而不是功率密度谱的方法，得到如果SFC方法应用后有一个谷意味着存在双成分（一个快的，一个慢的）信号，然后他们发现在选的266个BATSE暴中有93个暴有。
这个可以想想中间的原因。
难道就是那个看到的大的整体光变叠加一些小的毛刺？
精彩摘抄:
文章信息:
- · arXiv e-print (arXiv:1103.0074)
- · References in the Article
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| Title: |
| Evidence Of Superposed Variability Components In GRB Prompt Emission Lightcurves |
| Authors: |
| Gao, He; Zhang, Binbin; Zhang, Bing |
| Publication: |
| eprint arXiv:1103.0074 |
| Publication Date: |
| 02/2011 |
| Origin: |
| ARXIV |
| Keywords: |
| Astrophysics - High Energy Astrophysical Phenomena |
| Comment: |
| 12 pages, 5 figures, 1 table |
| Bibliographic Code: |
| 2011arXiv1103.0074G |
Abstract
Gamma-ray bursts (GRBs) have variable lightcurves. Although most models attribute the observed variability to one physical origin (e.g. central engine activity, clumpy circumburst medium, relativistic turbulence), some models invoke two physically distinct variability components. We develop a method, namely, the stepwise filter correlation (SFC) method, to decompose the variability components in a GRB lightcurve. Based on a low-pass filter technique, we progressively filter the high frequency signals from the lightcurve, and then perform a correlation analysis between each adjunct pair of filtered lightcurves. Our simulations suggest that if a mock lightcurve contains a "slow" variability component superposed on a rapidly varying time sequence, the correlation coefficient as a function of the filter frequency would display a prominent "dip" feature around the frequency of the slow component. Through simulations, we prove that this method is robust to catch the superposition signals that are otherwise not easy to retrieve based on other methods (e.g. the power density spectrum analysis method). We apply this new method to 266 BATSE bright GRBs. We find that 93 bursts have clear evidence of such a superposition effect. We perform a statistical analysis of the identied variability components, and discuss the physical implications for GRB physics.
