论文标题
快速无线电爆发的宿主星系中的分散度测量组件：FRB的统计特性的观察性约束
Dispersion measure components within host galaxies of Fast Radio Bursts: observational constraints from statistical properties of FRBs
论文作者
论文摘要
快速无线电爆发（FRB）的分散度度量（DM）通常用作距离的指标，假设DM超过了在每个FRB方向内超过银河系中预期量的DM，主要来自半乳酸间培养基。但是，如果例如，大多数FRB祖细胞嵌入了离子化的室外材料（CSM，例如超新星残留物）中，则假设可能并非如此。在这项研究中，我们使用FRB的分析模型共同分析了Parkes望远镜和澳大利亚平方公里阵列探路者（ASKAP）观察到的DM，通量密度和FRB样品的分布，以限制各种DM组件的分数，这些分数塑造了整体DM分布和FRBS的整体DM分布和发射特性。将模型预测与观察结果进行比较，我们发现每个FRB主机星系中的典型DM数量为$ \ sim 120 $ cm $^{ - 3} $ PC，自然可以解释为星际介质（ISM）和普通星系的晕圈的组合，而无需与离子化的CSM相关联，而无需与Iromized CSM相关联。此外，我们还发现，观察到的FRB的通量密度在统计学上不会遭受强大的$ K $ - 纠正，即FRB的典型光度密度在发射频率$ν_{\ rm REST} \ sim $ 1--4 GHz的范围内不会显着变化。
Dispersion measure (DM) of Fast Radio Bursts (FRBs) are commonly used as a indicator of distance assuming that DM in excess of the expected amount within the Milky Way in the direction of each FRB arise mostly from the inter-galactic medium. However, the assumption might not be true if, for example, most FRB progenitors are embedded in ionized circumstellar material (CSM, e.g. supernova remnant). In this study, we jointly analyze distributions of DM, flux density, and fluence of the FRB samples observed by the Parkes telescope and the Australian Square Kilometre Array Pathfinder (ASKAP) using analytical models of FRBs, to constrain fractions of various DM components that shape the overall DM distribution and emission properties of FRBs. Comparing the model predictions with the observations we find that the typical amount of DM in each FRB host galaxy is $\sim 120$ cm$^{-3}$pc which is naturally explained as a combination of interstellar medium (ISM) and halo of an ordinary galaxy, without additional contribution from ionized CSM that is directly associated with an FRB progenitor. Furthermore, we also find that observed flux densities of FRBs do not statistically suffer strong $K$-correction, i.e. the typical luminosity density of FRBs does not significantly change within the range of emitting frequency $ν_{\rm rest} \sim$ 1--4 GHz.
