Zappa Francesco, Bernuzzi Sebastiano, Radice David, Perego Albino, Dietrich Tim
Dipartimento di Scienze Matematiche Fisiche ed Informatiche, Universitá di Parma, I-43124 Parma, Italia.
Istituto Nazionale di Fisica Nucleare, Sezione Milano Bicocca, gruppo collegato di Parma, I-43124 Parma, Italia.
Phys Rev Lett. 2018 Mar 16;120(11):111101. doi: 10.1103/PhysRevLett.120.111101.
We study the gravitational-wave peak luminosity and radiated energy of quasicircular neutron star mergers using a large sample of numerical relativity simulations with different binary parameters and input physics. The peak luminosity for all the binaries can be described in terms of the mass ratio and of the leading-order post-Newtonian tidal parameter solely. The mergers resulting in a prompt collapse to black hole have the largest peak luminosities. However, the largest amount of energy per unit mass is radiated by mergers that produce a hypermassive neutron star or a massive neutron star remnant. We quantify the gravitational-wave luminosity of binary neutron star merger events, and set upper limits on the radiated energy and the remnant angular momentum from these events. We find that there is an empirical universal relation connecting the total gravitational radiation and the angular momentum of the remnant. Our results constrain the final spin of the remnant black hole and also indicate that stable neutron star remnant forms with super-Keplerian angular momentum.
我们使用具有不同双星参数和输入物理条件的大量数值相对论模拟样本，研究准圆形中子星合并的引力波峰值光度和辐射能量。所有双星的峰值光度仅能用质量比和领先阶后牛顿潮汐参数来描述。导致迅速坍缩成黑洞的合并具有最大的峰值光度。然而，产生超重质量中子星或大质量中子星残骸的合并辐射出的单位质量能量最大。我们对双中子星合并事件的引力波光度进行了量化，并设定了这些事件的辐射能量和残骸角动量的上限。我们发现存在一个将总引力辐射与残骸角动量联系起来的经验通用关系。我们的结果限制了残骸黑洞的最终自旋，还表明稳定的中子星残骸以超开普勒角动量形成。
