AI 中文总结
本研究针对即将建成的XSMT望远镜，构建了耦合抛射物动力学与非热同步辐射的数值框架，量化了双中子星并合亚毫米波对应体的可探测性与事件率，为引力波触发观测的优先级排序提供了定量依据。
AI 中文摘要
双中子星（BNS）并合的亚毫米波（sub-mm）后续观测能为相对论性外流的早期能量学特征与环境提供独特约束，可捕捉厘米波段辐射通常仍处于光学厚状态或尚未达到峰值的时期的光谱演化。然而，实际的科学产出取决于仪器的特定探测阈值、观测节奏，以及各向同性抛射物与准直相对论性喷流各自的时间演化贡献差异。随着即将建成的雪山牧场15米亚毫米波望远镜（XSMT）的投入使用，需要开展针对该设备的预测研究，以验证是否存在持续的引擎能量注入——这是长寿命磁星遗迹（而非即时形成的黑洞）的预期特征。我们提出了一个统一的数值框架，该框架将引擎驱动的抛射物动力学与非热同步辐射相耦合，同时考虑了同步自吸收和深牛顿效应。采用230/345/460 GHz频段下5σ（1小时积分）点源探测阈值分别为1.5/2.9/10.2 mJy的固定参数，我们构建了参数空间可探测性分布图，并基于当前的双中子星并合率先验值估算了事件发生率。对于距离为40 Mpc的基准局域事件，我们发现磁星增强的抛射物余辉在数周至数月的时间尺度上达到峰值，且可探测时间足够长，支持延迟后续观测；当f_mag=1时，230 GHz频段下的预期全天事件率为Ṇ_ej ≈ 0.05–1.7 yr⁻¹；该速率为上限值，且与长寿命磁星的占比呈线性关系。相比之下，尽管相对论性喷流会产生强烈的早期信号，但其探测受到窄准直角和短暂可见时间的限制。我们的框架为多信使时代下引力波触发事件的优先级排序以及最大化XSMT的科学产出提供了定量基础。
英文摘要
Submillimeter (sub-mm) follow-up of binary neutron star (BNS) mergers provides unique constraints on the early-time energetics and environments of relativistic outflows, capturing the spectral evolution at epochs where centimeter-band emission is often still optically thick or yet to peak. However, the practical scientific yield depends on instrument-specific thresholds, the observing cadence, and the distinct temporal contributions from isotropic ejecta versus beamed relativistic jets. With the upcoming Xue-shan-mu-chang 15-meter SubMillimeter Telescope (XSMT), facility-specific forecasts are needed to test for sustained engine energy injection, as expected for a long-lived magnetar remnant rather than a promptly formed black hole. We present a unified numerical framework that couples engine-driven ejecta dynamics to non-thermal synchrotron emission, accounting for synchrotron self-absorption and deep-Newtonian effects. Adopting fixed 5$σ$ (1 h) point-source thresholds of 1.5/2.9/10.2 mJy at 230/345/460 GHz, we construct parameter-space detectability maps and estimate event rates based on current BNS merger-rate priors. For a fiducial local event at 40 Mpc, we find that a magnetar-boosted ejecta afterglow peaks on timescales of weeks to months and remains detectable long enough to allow delayed follow-up, with an expected all-sky rate of $\dot N_{\rm ej} \approx 0.05$--1.7 yr$^{-1}$ at 230 GHz for $f_{\rm mag}=1$; this rate is an upper limit and scales linearly with the long-lived magnetar fraction. Conversely, while relativistic jets produce intense early-time signals, their detection is constrained by narrow beaming and fleeting visibility. Our framework provides a quantitative basis for prioritizing gravitational-wave triggers and maximizing the scientific yield of XSMT in the multi-messenger era.
Comments24 pages, 6 figures, accepted by ApJ
