arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1010.2087astro-ph.HEastro-ph.CO
收藏

第三类伽马射线暴的一个明显的峰值通量分布:一个可能的X射线闪光的特征?

A distinct peak-flux distribution of the third class of gamma-ray bursts: A possible signature of X-ray flashes?

P. Veres, Z. Bagoly, I. Horváth, A. Mészáros, L. G. Balázs

摘要:

伽马射线暴是宇宙中最明亮的事件。超越短-长分类方案,我们在三个突发人群的背景下工作,第三组中间持续时间和最软的频谱。我们正在寻找的物理特性,区分中间持续时间的爆发,从其他两个类。我们使用极大似然拟合来建立持续时间-硬度平面中的组成员。为了证实这些结果,我们还使用了k-means和层次聚类。我们使用蒙特卡罗模拟来测试中间组存在的意义,我们发现它与99.8%的概率。中间持续时间群体具有显著较低的峰值流量(具有99.94%的显著性)。此外,测量到红移的长爆发比没有测量到红移的长爆发有更高的峰值通量(98.6%的显著性)。由于第三组是最软的,我们认为,我们有{相关}它们与X射线闪烁之间的伽马射线暴。我们给这类事件一个新的概率定义。

英文摘要:

Gamma-ray bursts are the most luminous events in the Universe. Going beyond the short-long classification scheme we work in the context of three burst populations with the third group of intermediate duration and softest spectrum. We are looking for physical properties which discriminate the intermediate duration bursts from the other two classes. We use maximum likelihood fits to establish group memberships in the duration-hardness plane. To confirm these results we also use k-means and hierarchical clustering. We use Monte-Carlo simulations to test the significance of the existence of the intermediate group and we find it with 99.8% probability. The intermediate duration population has a significantly lower peak-flux (with 99.94% significance). Also, long bursts with measured redshift have higher peak-fluxes (with 98.6% significance) than long bursts without measured redshifts. As the third group is the softest, we argue that we have {related} them with X-ray flashes among the gamma-ray bursts. We give a new, probabilistic definition for this class of events.

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。

↑