标题： 磁流体动力学模拟非同心双中子星合并 显示英文标题

标题： Magneto-Hydrodynamic Simulations of Eccentric Binary Neutron Star Mergers

摘要： 高偏心率双中子星并合在引力波信号和物质抛射方面与准圆轨道的并合表现出独特的动态和观测特征，导致不同的电磁对应体。 在本文中，我们展示了双中子星系统在高偏心轨道上的广义相对论磁流体动力学模拟。 在准圆轨道双星中，磁场的影响太弱，无法影响一般的并合前动力学，而偏心系统中的近距离相遇可能会引发磁流体动力学不稳定性。 因此，我们研究了三种不同初始偏心率系统的并合前、并合中和并合后的可能影响。 我们研究了近距离相遇中由潮汐相互作用激发的f模振荡，并发现与预测的f模频率估计有很好的一致性。 然而，我们的模拟显示，与忽略磁场的结果相比没有显著差异。 尽管我们在恒星内部观察到磁场环向结构的重新排列，但在相遇过程中磁场能量没有显著增加。 此外，在并合过程中，磁场的增强似乎在我们的系统中很大程度上与偏心率无关。 与研究非磁化双中子星并合的成果一致，我们发现偏心率与质量抛射之间存在相关性，较大的碰撞参数会导致更多的未束缚物质。 显示英文摘要

摘要： Highly eccentric binary neutron star mergers exhibit unique dynamical and observational signatures compared to quasi-circular ones in terms of their gravitational wave signal and the ejection of matter, leading to different electromagnetic counterparts. In this article, we present general relativistic magneto-hydrodynamic simulations of binary neutron star systems on highly eccentric orbits. While in quasi-circular binaries, the influence of the magnetic field is too weak to affect the general pre-merger dynamics, the close encounters in eccentric systems could potentially trigger magneto-hydrodynamic instabilities. Therefore, we investigate possible effects before, during, and after the merger for a total of three different systems with varying initial eccentricity. We study the f-mode oscillations excited by tidal interaction in close encounters and find good agreement with predicted f-mode frequency estimates. However, our simulations reveal no significant differences compared to results neglecting the magnetic field. Although we observe a rearrangement of the poloidal structure of the magnetic field inside the stars, there is no relevant increase in the magnetic energy during the encounters. Also, during the merger, the amplification of the magnetic field seems to be largely independent of the eccentricity in our systems. Consistent with studies of merging non-magnetized binary neutron stars, we find a correlation between eccentricity and mass ejection, with a higher impact parameter leading to a larger amount of unbound material.