THE CORRELATION BETWEEN DISPERSION MEASURE AND X-RAY COLUMN DENSITY FROM RADIO PULSARS
THE CORRELATION BETWEEN DISPERSION MEASURE AND X-RAY COLUMN DENSITY FROM RADIO PULSARS
复制标题
DOI：
10.1088/0004-637x/768/1/64
复制
发表时间：
2013-03
期刊：
影响因子：
--
通讯作者：
C. He;C. He;Cherry Ng;Cherry Ng;V. Kaspi
中科院分区：
文献类型：
--
作者：
C. He;C. He;Cherry Ng;Cherry Ng;V. Kaspi
脉冲星是一种非凡的物体，它在整个电磁光谱中发射，为星际介质提供了一个强大的探测器。在这项研究中，我们利用钱德拉X射线天文台或XMM-牛顿天文台在X射线能量下探测到的68颗射电脉冲星，研究了色散测量(DM)与X射线吸收柱密度NH之间的关系。我们找到了一个最适合的经验线性关系，它对应于平均电离度%，证实了文献中通常假设的每10个中性氢原子中有一个自由电子的比率。我们还比较了不同的NH估计，并注意到从X射线观测获得的一些NH值高于沿同一视线的银河系HI柱总密度，而光学消光通常给出最好的NH预测。
Pulsars are remarkable objects that emit across the entire electromagnetic spectrum, providing a powerful probe of the interstellar medium. In this study, we investigate the relation between dispersion measure (DM) and X-ray absorption column density NH using 68 radio pulsars detected at X-ray energies with the Chandra X-Ray Observatory or XMM-Newton. We find a best-fit empirical linear relation of , which corresponds to an average ionization of %, confirming the ratio of one free electron per 10 neutral hydrogen atoms commonly assumed in the literature. We also compare different NH estimates and note that some NH values obtained from X-ray observations are higher than the total Galactic H i column density along the same line of sight, while the optical extinction generally gives the best NH predictions.