arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 0809.1389astro-ph
收藏

X射线中伽马射线暴的时光关联

A time - luminosity correlation for Gamma Ray Bursts in the X - rays

M. G. Dainotti, V. F. Cardone, S. Capozziello

摘要:

伽马射线暴(GRB)作为一种将哈勃图扩展到极高红移的可能途径,近来引起了人们的广泛关注。然而,它们的内在性质的大的分散性阻止了直接使用它们作为距离指示器,因此寻找涉及可观测性质的关系以标准化伽马射线暴是开放的,就像菲利普斯定律使得可以使用Ia型超新星(SNeIa)作为可测量的蜡烛一样。我们在这里使用的数据X射线衰变曲线和光谱指数的样本伽玛暴观测与雨燕卫星。这些数据被用作贝叶斯统计分析的输入,以寻找余辉曲线的X射线光度L_X(T_a)和时间常数T_a之间的相关性。我们发现\log{[L_X(T_a)]}和\log{[T_a/(1+z)]}之间的线性关系与内在的散射sigma_{int} = 0.33以前报道的关系。值得注意的是,无论是斜率和内在的散射几乎是独立的物质密度Omega_M和常数状态方程的暗能量分量,从而表明圆形问题是缓解了$L_X - T_a$关系。

英文摘要:

Gamma ray bursts (GRBs) have recently attracted much attention as a possible way to extend the Hubble diagram to very high redshift. However, the large scatter in their intrinsic properties prevents directly using them as distance indicator so that the hunt is open for a relation involving an observable property to standardize GRBs in the same way as the Phillips law makes it possible to use Type Ia Supernovae (SNeIa) as standardizable candles. We use here the data on the X - ray decay curve and spectral index of a sample of GRBs observed with the Swift satellite. These data are used as input to a Bayesian statistical analysis looking for a correlation between the X - ray luminosity L_X(T_a) and the time constant T_a of the afterglow curve. We find a linear relation between \log{[L_X(T_a)]} and \log{[T_a/(1+z)]} with an intrinsic scatter sigma_{int} = 0.33 comparable to previously reported relations. Remarkably, both the slope and the intrinsic scatter are almost independent on the matter density Omega_M and the constant equation of state w of the dark energy component thus suggesting that the circularity problem is alleviated for the $L_X - T_a$ relation.

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。

↑