标题： 合并后双中子星引力波信号的光谱特性 显示英文标题

标题： Spectral properties of the post-merger gravitational-wave signal from binary neutron stars

摘要： 在多位作者之前工作的基础上，我们最近提出了一种新方法，利用合并中子星双星产生的引力波探测，可以确定核密度下物质的状态方程，从而确定中子星的结构。 特别是，在对具有核状态方程的双星进行了大量数值相对论模拟后，我们发现合并后的辐射具有两个明显且稳健的光谱特征。 虽然高频峰已被证明与合并产生的超大质量中子星的振荡有关，并依赖于状态方程，但我们指出低频峰与合并过程以及双星中恒星的总致密性有关。 这种关系基本上是普适的，并为设置状态方程的严格约束提供了强大工具。 我们在此提供关于所进行的广泛分析的额外信息，说明了使用的方法、考虑的测试以及结果的稳健性。 我们还讨论了在探索数据时可以推导出的其他关系，以及这些关系如何与双星的各种特性相关联。 最后，我们提出一个简单的机械玩具模型，可以解释合并后信号的主要光谱特征，甚至可以解析地再现合并后发出的复杂波形。 显示英文摘要

摘要： Extending previous work by a number of authors, we have recently presented a new approach in which the detection of gravitational waves from merging neutron star binaries can be used to determine the equation of state of matter at nuclear density and hence the structure of neutron stars. In particular, after performing a large number of numerical-relativity simulations of binaries with nuclear equations of state, we have found that the post-merger emission is characterized by two distinct and robust spectral features. While the high-frequency peak was already shown to be associated with the oscillations of the hypermassive neutron star produced by the merger and to depend on the equation of state, we have highlighted that the low-frequency peak is related to the merger process and to the total compactness of the stars in the binary. This relation is essentially universal and provides a powerful tool to set tight constraints on the equation of state. We here provide additional information on the extensive analysis performed, illustrating the methods used, the tests considered, as well as the robustness of the results. We also discuss additional relations that can be deduced when exploring the data and how these correlate with various properties of the binary. Finally, we present a simple mechanical toy model that explains the main spectral features of the post-merger signal and can even reproduce analytically the complex waveforms emitted right after the merger.