Measuring quasinormal mode amplitudes with misaligned binary black hole ringdowns
Measuring quasinormal mode amplitudes with misaligned binary black hole ringdowns
复制标题
DOI：
10.1103/physrevd.105.124030
复制
发表时间：
2022-04
影响因子：
5
通讯作者：
Halston Lim;S. Hughes;G. Khanna
中科院分区：
文献类型：
--
作者：
Halston Lim;S. Hughes;G. Khanna
在最近的工作中，我们研究了如何在双星合并的环衰阶段的不同模式被激发作为一个函数的最终暴跌几何。至少在大质量比极限下，我们发现了描述暴跌的角度与构成环衰的不同准正模态（QNMs）振幅之间的清晰映射。在本研究中，我们使用该映射来构建一个波形模型，该模型表示为QNMs的总和，其中模态振幅和相位由源跳入参数决定。我们首先生成大量的校准波形，并在每个模态振幅和相位的拟合之间进行插值，直至$\ell \leq 8$和$\ell - |m| \leq 4$。我们的校准数据的密度使我们能够解决重要的特征，如大错位时的相变不连续。使用我们的环衰波形模型，然后使用添加高斯白噪声的贝叶斯参数估计来证明，原则上，模态振幅可以测量并用于约束暴跌几何形状。我们发现，通过引入先验信息约束模式激励，推理得到了极大的改善，这促使人们理解和表征QNM激励如何依赖于聚并几何形状。这些结果是绘制任意质量和自旋激发模式的更广泛努力的一部分，这将有助于在即将到来的引力波测量中表征环衰波。
In recent work, we examined how different modes in the ringdown phase of a binary coalescence are excited as a function of the final plunge geometry. At least in the large mass ratio limit, we found a clean mapping between angles describing the plunge and the amplitude of different quasi-normal modes (QNMs) which constitute the ringdown. In this study, we use that mapping to construct a waveform model expressed as a sum of QNMs where the mode amplitudes and phases are determined by the source plunge parameters. We first generate a large number of calibration waveforms and interpolate between fits of each mode amplitude and phase up to $\ell \leq 8$ and $\ell - |m| \leq 4$. The density of our calibration data allows us to resolve important features such as phase transition discontinuities at large misalignments. Using our ringdown waveform model, we then perform Bayesian parameter estimation with added white Gaussian noise to demonstrate that, in principle, the mode amplitudes can be measured and used to constrain the plunge geometry. We find that inferences are substantially improved by incorporating prior information constraining mode excitation, which motivates work to understand and characterize how the QNM excitation depends on the coalescence geometry. These results are part of a broader effort to map the mode excitation from arbitrary masses and spins, which will be useful for characterizing ringdown waves in upcoming gravitational-wave measurements.