Siemonsen Nils
Princeton Gravity Initiative, <a href="https://ror.org/00hx57361">Princeton University</a>, Princeton, New Jersey 08544, USA and Department of Physics, <a href="https://ror.org/00hx57361">Princeton University</a>, Princeton, New Jersey 08544, USA.
Phys Rev Lett. 2024 Jul 19;133(3):031401. doi: 10.1103/PhysRevLett.133.031401.
We perform the first nonlinear and self-consistent study of the merger and ringdown of a black hole mimicking object with stable light rings. To that end, we numerically solve the full Einstein-Klein-Gordon equations governing the head-on collisions of a series of binary boson stars in the large-mass-ratio regime resulting in spinning horizonless remnants with stable light rings. We broadly confirm the appearance of features in the extracted gravitational waveforms expected based on perturbative methods: the signal from the prompt response of the remnants approaches that of a Kerr black hole in the large-compactness limit, and the subsequent emissions contain periodically appearing bursts akin to so-called gravitational wave echoes. However, these bursts occur at high frequencies and are sourced by perturbations of the remnant's internal degrees of freedom. Furthermore, the emitted waveforms also contain a large-amplitude and long-lived component comparable in frequency to black hole quasinormal modes. We further characterize the emissions, obtain basic scaling relations of relevant timescales, and compute the energy emitted in gravitational waves.
我们对具有稳定光环的黑洞模拟物体的合并和铃宕进行了首次非线性和自洽研究。为此，我们数值求解了完整的爱因斯坦 - 克莱因 - 戈登方程，该方程描述了一系列大质量比情况下的双玻色子星正面碰撞，产生了具有稳定光环的旋转无视界残骸。我们大致证实了基于微扰方法预期的提取引力波形中特征的出现：残骸即时响应的信号在大紧致性极限下接近克尔黑洞的信号，随后的辐射包含周期性出现的爆发，类似于所谓的引力波回声。然而，这些爆发发生在高频，并且由残骸内部自由度的扰动引起。此外，发射的波形还包含一个频率与黑洞准正则模相当的大振幅且长寿命的分量。我们进一步对辐射进行了表征，获得了相关时间尺度的基本标度关系，并计算了引力波中发射的能量。
