High‐resolution calculations of merging neutron stars – II. Neutrino emission
High‐resolution calculations of merging neutron stars – II. Neutrino emission
复制标题
合并中子星的高分辨率计算 – II。
DOI：
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
M. Liebendörfer
中科院分区：
文献类型：
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作者：
S. Rosswog;M. Liebendörfer
两颗中子星合并产生的残余物会产生大量的中微子。在本文中，我们提出了中微子发射的结果，通过牛顿，高分辨率模拟的合并事件。这些模拟使用三维光滑粒子流体力学与核，温度依赖的状态方程和多味中微子泄漏计划。我们提出了我们的计划的细节，讨论了中微子发射的中子星星合并的结果，并比较他们的核心坍缩超新星的情况下，中微子发射已经研究了几十年。中微子的平均能量与超新星的情况相似，但与后者相反，光度主要由电子型反中微子控制，这些反中微子产生于合并残余物的热的、富含中子的厚圆盘中。这个圆盘较冷的部分含有相当大比例的重核，然而，这并不显著影响整个中微子发射结果。我们的总中微子光度从合并事件是相当低的，比以前的调查中发现的。这就限制了中子星星合并通过中微子湮灭产生伽马射线暴的能力。中微子优先沿着初始的双星旋转轴发射，在“极上”看到的事件在中微子中会比在“边缘上”看到的类似事件亮得多。
The remnant resulting from the merger of two neutron stars produces neutrinos in copious amounts. In this paper we present the neutrino emission results obtained via Newtonian, high-resolution simulations of the coalescence event. These simulations use three-dimensional smoothed particle hydrodynamics together with a nuclear, temperature-dependent equation of state and a multiflavour neutrino leakage scheme. We present the details of our scheme, discuss the neutrino emission results from a neutron star coalescence and compare them with the core-collapse supernova case where neutrino emission has been studied for several decades. The average neutrino energies are similar to those in the supernova case, but contrary to the latter, the luminosities are dominated by electron-type antineutrinos that are produced in the hot, neutron-rich, thick disc of the merger remnant. The cooler parts of this disc contain substantial fractions of heavy nuclei, which, however, do not influence the overall neutrino emission results significantly. Our total neutrino luminosities from the merger event are considerably lower than those found in previous investigations. This imposes constraints on the ability of neutron star mergers to produce a gamma-ray burst via neutrino annihilation. The neutrinos are emitted preferentially along the initial binary rotation axis, an event seen ‘pole-on’ would appear much brighter in neutrinos than a similar event seen ‘edge-on’.