Effects of the microphysical Equation of State in the mergers of magnetized Neutron Stars With Neutrino Cooling
Effects of the microphysical Equation of State in the mergers of magnetized Neutron Stars With Neutrino Cooling
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DOI：
10.1103/physrevd.92.044045
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发表时间：
2015-05
影响因子：
5
通讯作者：
C. Palenzuela;S. Liebling;D. Neilsen;Luis Lehner;O. L. Caballero;E. O’Connor;Matthew Anderson
中科院分区：
文献类型：
--
作者：
C. Palenzuela;S. Liebling;D. Neilsen;Luis Lehner;O. L. Caballero;E. O’Connor;Matthew Anderson
我们使用不同的现实微物理核状态方程，并结合磁场和中微子冷却效应，研究了双中子星的并合。特别地，我们集中在状态方程对引力波特征的影响，以及它的作用，结合冷却和电磁效应，在确定由合并产生的超大质量中子星的性质，中微子的产生，以及系统喷射物的特征。我们发现的弹射与最近的其他研究一致，即软状态方程比硬状态方程产生更多的弹射。此外，在较软的状态方程中，中子丰富度增加。根据报道的千新星观测（与GRB~130603B和GRB~060614有关）和深海沉积物中相对低丰度的重放射性元素的发现（相对于可能通过超新星产生），我们推测，如果这些事件是由双中子星合并驱动的，那么软EoS可能是首选-因为它产生足够丰富的中子抛射物。我们还发现，实际的磁场强度，通过调整子网格模型来捕捉合并时的开尔文-亥姆霍兹不稳定性产生的磁放大，通常太弱，无法在大约10美元~ms的时间尺度内影响合并后的引力波特征，但可能对合并后的动力学产生微妙的影响。
We study the merger of binary neutron stars using different realistic, microphysical nuclear equations of state, as well as incorporating magnetic field and neutrino cooling effects. In particular, we concentrate on the influence of the equation of state on the gravitational wave signature and also on its role, in combination with cooling and electromagnetic effects, in determining the properties of the hypermassive neutron star resulting from the merger, the production of neutrinos, and the characteristics of ejecta from the system. The ejecta we find are consistent with other recent studies that find soft equations of state produce more ejecta than stiffer equations of state. Moreover, the degree of neutron richness increases for softer equations of state. In light of reported kilonova observations (associated to GRB~130603B and GRB~060614) and the discovery of relatively low abundances of heavy, radioactive elements in deep sea deposits (with respect to possible production via supernovae), we speculate that a soft EoS might be preferred---because of its significant production of sufficiently neutron rich ejecta---if such events are driven by binary neutron star mergers. We also find that realistic magnetic field strengths, obtained with a sub-grid model tuned to capture magnetic amplification via the Kelvin-Helmholtz instability at merger, are generally too weak to affect the gravitational wave signature post-merger within a time scale of $\approx 10$~ms but can have subtle effects on the post-merger dynamics.