arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0812.3349astro-ph
收藏

INTEGRAL伽马射线暴的更新谱表

The updated spectral catalogue of INTEGRAL Gamma-Ray Bursts

G. Vianello, D. Götz, S. Mereghetti

摘要:

我们提出了一个目录的所有突发检测和本地化的IBIS仪器板上的INTEGRAL卫星从2002年11月至2008年9月的属性。样本由56个爆发组成,相当于每月约0.8个GRB。由于INTEGRAL爆发警报系统的性能,50%的IBIS伽玛暴探测到了余辉,而5%的伽玛暴有红移测量。使用最新的软件和校准对INTEGRAL公共档案中的43个爆发进行了光谱分析,得出了一个更新的、均匀的和准确的样本光谱特征目录。在可能的情况下,还进行了时间分辨光谱分析。样品中的伽玛射线暴具有20-200 keV的能量密度,范围为5 x 1 E-8 - 2.5 x 1 E-4 erg cm-2,峰值通量范围为0.11 - 56 ph cm-2 s-1。虽然大多数的光谱都很好地拟合的幂律与光子指数~ 1.6,我们发现,9爆发更好地描述了截止幂律,导致在35- 190 keV的范围内的Ep值。尽管这些结果与Swift上BAT获得的结果相当,但有一个边际证据表明ISGRI检测到的爆发比Swift/BAT更暗。使用修订的光谱参数和更新的天空曝光图,也考虑到GRB触发效率的影响,我们加强了与长光谱滞后的微弱爆发的超星系平面的空间相关性的证据(Foley等人,2008年)。

英文摘要:

We present a catalogue with the properties of all the bursts detected and localized by the IBIS instrument onboard the INTEGRAL satellite from November 2002 to September 2008. The sample is composed of 56 bursts, corresponding to a rate of ~ 0.8 GRB per month. Thanks to the performances of the INTEGRAL Burst Alert System, 50% of the IBIS GRBs have detected afterglows, while 5% have redshift measurements. A spectral analysis of the 43 bursts in the INTEGRAL public archive has been carried out using the most recent software and calibration, deriving an updated, homogeneous and accurate catalogue with the spectral features of the sample. When possible also a time-resolved spectral analysis has been carried out. The GRBs in the sample have 20-200 keV fluences in the range 5 x 1E-8 --2.5 x 1E-4 erg cm-2, and peak fluxes in the range 0.11 - 56 ph cm-2 s-1. While most of the spectra are well fitted by a power law with photon index ~ 1.6, we found that 9 bursts are better described by a cut-off power law, resulting in Ep values in the range 35--190 keV. Altough these results are comparable with those obtained with BAT onboard Swift, there is a marginal evidence that ISGRI detects dimmer bursts than Swift/BAT. Using the revised spectral parameters and an updated sky exposure map that takes into account also the effects of the GRB trigger efficiency, we strengthen the evidence for a spatial correlation with the super galactic plane of the faint bursts with long spectral lag (Foley et al.,2008).

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑