Detectability of radio afterglows from binary neutron star mergers and implications for fast radio bursts
Detectability of radio afterglows from binary neutron star mergers and implications for fast radio bursts
复制标题
DOI：
10.1093/mnras/staa2418
复制
发表时间：
2020-09
影响因子：
4.8
通讯作者：
Haoxiang Lin;T. Totani
中科院分区：
文献类型：
--
作者：
Haoxiang Lin;T. Totani
双中子星(BNS)合并是重复和非重复快速射电爆发(FRB)的可能来源之一，FRB与引力波和短伽马射线暴(GRB)有关。在这项工作中，我们探索了来自BNS合并的射电余辉的可探测性，并将其与观测到的FRB余辉的射电极限进行了比较。我们计算了由相对论喷流和较慢的各向同性喷射物两部分提供能量的余辉通量，并量化了探测几率作为源红移、观测时间和通量灵敏度的函数。模型参数分布采用从短伽玛暴余辉推断的模型参数分布，并假定视角分布(均匀球面、引力波、轴上偏置)以反映不同的搜索场景。假设FRB不是强束的，我们与报道的射电极限探测的FRB进行比较，发现探测概率一般为1-10%，因此考虑到各向同性分量的小样本数(在10$\MU$Jy灵敏度下为20%)，合并后1-10年左右达到峰值，因此对BNS前体模型不是很强的约束。因此，对这些物体的持久无线电发射进行长期无线电监测是重要的。
Binary neutron star (BNS) mergers are one of the proposed origins for both repeating and non-repeating fast radio bursts (FRBs), which associates FRBs with gravitational waves and short gamma-ray bursts (GRBs). In this work, we explore detectability of radio afterglows from BNS mergers and compare it to the observed radio limits on FRB afterglows. We calculate the afterglow flux powered by the two components: a relativistic jet and a slower isotropic ejecta, and quantify the detection probability as a function of the source redshift, observing time, and flux sensitivity. The model parameter distributions inferred from short GRB afterglows are adopted, and viewing angle distributions (uniform spherical, gravitational-wave, on-axis biased) are assumed to reflect different searching scenario. Assuming that FRBs are not strongly beamed, we make comparison to FRBs detected with reported radio limits and find the detection probabilities are 1--10% in general, and hence not a strong constraint on the BNS progenitor model considering the small sample number ( 20% at 10$\mu$Jy sensitivity) for the isotropic component that would peak around $\sim$1--10 years after the merger. Therefore a long term radio monitoring of persistent radio emission for these objects is important.