标题： 中子星合并模拟对中微子输运和中微子-物质相互作用变化的鲁棒性 显示英文标题

标题： Robustness of neutron star merger simulations to changes in neutrino transport and neutrino-matter interactions

摘要： 双中子星合并在核天体物理中起着重要作用：它们的引力波和电磁信号携带了关于核饱和密度以上冷物质状态方程的信息，它们可能是宇宙中r过程元素的主要来源之一。 在合并期间和之后，中微子与物质的相互作用会影响这些电磁信号的特性以及所产生的r过程元素的相对丰度。 然而，现有的合并模拟在真实模拟中微子传输和中微子-物质相互作用方面能力有限。 在这里，我们比较了使用最先进的两矩量或蒙特卡罗传输方案对单个双中子星系统（$(5-10)\,{\rm ms}$）的合并模拟结果的影响。 我们还研究了在模拟中使用不同的反应速率。 虽然最佳传输方案通常在中微子对系统定性影响上达成一致，但高密度区域行为的差异可能会显著影响该亚稳态合并残余物的坍缩时间和热潮汐臂的特性。 所选择的相互作用速率、传输算法以及Radice等人对两矩量算法的最新改进都可以导致合并残余物和流出物整体特性的变化达到$(10-30)\%$水平。 由Radice等人修复的先前矩量方案的限制也足以解释我们在之前比较蒙特卡罗和矩量方案时，在低质量双中子星系统背景下观察到的重轻子中微子产生方面的巨大差异。 显示英文摘要

摘要： Binary neutron star mergers play an important role in nuclear astrophysics: their gravitational wave and electromagnetic signals carry information about the equation of state of cold matter above nuclear saturation density, and they may be one of the main sources of r-process elements in the Universe. Neutrino-matter interactions during and after merger impact the properties of these electromagnetic signals, and the relative abundances of the produced r-process elements. Existing merger simulations are however limited in their ability to realistically model neutrino transport and neutrino-matter interactions. Here, we perform a comparison of the impact of the use of state-of-the art two-moment or Monte-Carlo transport schemes on the outcome of merger simulations, for a single binary neutron star system with a short-lived neutron star remnant ($(5-10)\,{\rm ms}$). We also investigate the use of different reaction rates in the simulations. While the best transport schemes generally agree well on the qualitative impact of neutrinos on the system, differences in the behavior of the high-density regions can significantly impact the collapse time and the properties of the hot tidal arms in this metastable merger remnant. The chosen interaction rates, transport algorithm, as well as recent improvements by Radice et al to the two-moment algorithms can all contribute to changes at the $(10-30)\%$ level in the global properties of the merger remnant and outflows. The limitations of previous moment schemes fixed by Radice et al also appear sufficient to explain the large difference that we observed in the production of heavy-lepton neutrinos in a previous comparison of Monte-Carlo and moment schemes in the context of a low mass binary neutron star system.