Repeated faint quasinormal bursts in extreme-mass-ratio inspiral waveforms: Evidence from frequency-domain scalar self-force calculations on generic Kerr orbits
Repeated faint quasinormal bursts in extreme-mass-ratio inspiral waveforms: Evidence from frequency-domain scalar self-force calculations on generic Kerr orbits
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DOI：
10.1103/physrevd.100.064008
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发表时间：
2019-05
影响因子：
5
通讯作者：
Zachary Nasipak;Thomas Osburn;C. Evans
中科院分区：
文献类型：
--
作者：
Zachary Nasipak;Thomas Osburn;C. Evans
我们报告的代码来计算标量带电粒子上的克尔时空中的一般束缚轨道运动的标量自作用力的发展。标量自作用力模型允许快速发展的计算技术相关的通用引力极值质量比的inspirals（EMRI）。我们的频域计算是用\textsc{Mathematica}编写的任意数值精度代码进行的。我们扩展光谱源集成技术的克尔时空，提高计算效率。我们的模型轨道几乎任意倾角$0\leq\iota<\pi/2$和偏心率高达$e \lesssim 0.8$。这一努力扩展了沃伯顿和巴拉克早期的工作，其中运动被限制在赤道平面或倾斜的球形轨道。与Thornburg和Wardell \cite{ThorWard 17}在时域计算中的最新发现一致，我们在围绕快速旋转黑洞的高偏心轨道的径向向外部分期间观察到自作用力振荡。如前所述，这些振荡反映了在近心通过期间激发的准正规模式耦合到自作用力中。我们的研究结果证实了频域代码的效果。{更重要的是，我们发现，准正常爆发（QNB）直接出现在波形后，每一个近星点通过。}这些微弱的爆发被证明是最小阻尼泛音的叠加（即，基本的）至少四个（$l=m \le 4$）准正规模。我们的研究结果表明，QNB应该出现在引力波形，从而提供规范不变的信号。在高信噪比EMRI中可能可观察到，QNB将为参数估计问题提供高频分量，其将补充波形的低频元素。
We report development of a code to calculate the scalar self-force on a scalar-charged particle moving on generic bound orbits in the Kerr spacetime. The scalar self-force model allows rapid development of computational techniques relevant to generic gravitational extreme-mass-ratio inspirals (EMRIs). Our frequency-domain calculations are made with arbitrary numerical precision code written in \textsc{Mathematica}. We extend spectral source integration techniques to the Kerr spacetime, increasing computational efficiency. We model orbits with nearly arbitrary inclinations $0\leq\iota<\pi/2$ and eccentricities up to $e \lesssim 0.8$. This effort extends earlier work by Warburton and Barack where motion was restricted to the equatorial plane or to inclined spherical orbits. Consistent with a recent discovery by Thornburg and Wardell \cite{ThorWard17} in time-domain calculations, we observe self-force oscillations during the radially-outbound portion of highly eccentric orbits around a rapidly rotating black hole. As noted previously, these oscillations reflect coupling into the self-force by quasinormal modes excited during pericenter passage. Our results confirm the effect with a frequency-domain code. \emph{More importantly, we find that quasinormal bursts (QNBs) appear directly in the waveform following each periastron passage.} These faint bursts are shown to be a superposition of the least-damped overtone (i.e., fundamental) of at least four ($l=m \le 4$) quasinormal modes. Our results suggest that QNBs should appear in gravitational waveforms, and thus provide a gauge-invariant signal. Potentially observable in high signal-to-noise ratio EMRIs, QNBs would provide high-frequency components to the parameter estimation problem that would complement low-frequency elements of the waveform.