Production of Jets Before Neutron Star Mergers
中子星并合前的喷流产生
We demonstrate that magnetospheric interactions between merging neutron stars (NSs) generate dual-jetted current outflows, analogous to the Alfvén wings observed during planetary interactions in the solar system. Using three-dimensional relativistic MHD simulations, we model the interaction as a conducting sphere moving through a highly magnetized plasma of the companion's magnetosphere. Unusually, the interaction operates in a regime that is relativistic yet sub-Alfvénic. Electromagnetic draping amplifies magnetic fields in a narrow layer near the stellar surface, leading to the generation of electric currents along the local magnetic field. The generation of beamed outflows enhances the instantaneous power of the pulsar-like radio and high-energy emission, produces spin/orbital modulations, and is likely to lead to observable precursor emission preceding the main gravitational wave event.
展开 ▾首次在相对论亚阿尔芬条件下模拟中子星磁层相互作用,发现了与行星磁层Alfvén翅膀相似的准直电流结构,预测该过程可产生脉冲星样束流辐射,为并合前兆探测提供新途径。
中子星并合产生的电磁前兆辐射是多信使天文学的重要目标。早期工作探讨了轨道运动中磁层感应电场驱动的单极感应器模型(Hansen+ 2001;Lai 2012),Lyutikov+ 2019进一步分析了单磁化和双磁化情形,指出磁层再激活可能产生可探测的射电和高能前兆。本文在此基础上,通过三维相对论磁流体力学模拟,首次揭示了相对论亚阿尔芬条件下导电中子星在伴星磁层中运动时形成的Alfvén翅膀电流结构,该结构与行星磁层中的经典Alfvén翅膀现象(Gold 1962;Drell+ 1965;Neubauer 1980)相似,但处于极端相对论边界条件。模拟表明,这些准直的电流通道伴随增强的电磁能量通量,可能驱动束流发射,为观测提供重要特征。未来研究应结合电阻磁流体力学和粒子模拟,探究电流耗散和相干辐射机制,并发展双磁化中子星和更极端相对论情形的模型,以更准确预测并合前兆的时间和谱特征。
预印本 2026-02-15 · 接收 2026-06-09 · 刊出 2026-07-14 · 收录 2026-07-22