Probing Binary Neutron Star Merger Ejecta and Remnants with Gravitational-wave and Radio Observations
用引力波与射电观测探测双中子星并合抛射物和遗迹
We present a study aimed at quantifying the detectability of radio counterparts of binary neutron star (BNS) mergers with total masses ≲3 M<SUB>⊙</SUB>, which may form neutron star remnants. We focus on mergers localized by gravitational-wave (GW) observations to sky areas ≲10 deg<SUP>2</SUP>, a precision that greatly facilitates optical counterpart identification and enables radio discovery even without detections at other wavelengths. Widely separated GW detectors are essential for building samples of well-localized BNS mergers accessible to radio telescopes, with minimum yearly detection rates (assuming the smallest values of the BNS local merger rate) ranging from a few with current GW detectors to hundreds with next-generation GW instruments. Current GW networks limit well-localized detections to z ≲ 0.2, while next-generation GW detectors extend the reach to z ≲ 0.8, encompassing the median redshift of short gamma-ray bursts (GRBs). With next-generation radio arrays operating at several tens of GHz and providing an order of magnitude improvement in sensitivity compared to the most sensitive ones available today, short GRB-like jet afterglows can be detected for a large fraction of the considered BNS mergers. At lower radio frequencies, detections with current radio interferometric arrays are feasible, though subject to synchrotron self-absorption effects. The enhanced sensitivity and survey speed of future radio interferometers operating at a few GHz, combined with the higher detection rate of well-localized BNSs enabled by next-generation GW observatories, are key to probing disk-wind and dynamical ejecta afterglows, as well as remnant diversity.
展开 ▾把新一代引力波网络定位与下一代射电阵列灵敏度自洽结合,针对多种抛射物组分给出可比探测率,并强调宽间距探测器网络(如 CE40-ET-A)对构建可射电跟踪的良定位样本至关重要。
此前 Gupta+ 2024 的统一双中子星种群模拟和 Kalogera+ 2024 推荐的下一代引力波网络概念已为探测前景评估提供基础;本文进一步用 Coughlin+ 2019 的抛射物质量/速度拟合与 Sarin+ 2022 的磁星注入模型,把链条延伸到射电对应体。随着 CE/ET 与 ngVLA/DSA-2000 投入使用,宽间距探测器网络可把良定位样本从每年几十个提升到数千个,使短伽马暴喷流余辉和千新星抛射物从单例转向大样本统计。Pandey+ 2025 已验证 Fisher 近似在信噪比与定位面积估计上的可靠性,未来可结合贝叶斯参数估计和真实射电巡天数据进一步细化这些预测。
预印本 2025-06-28 · 接收 2026-06-18 · 刊出 2026-07-28 · 收录 2026-08-20