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arXiv 0812.0069gr-qcastro-ph.SR
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准圆吸气紧双星引力波记忆的后牛顿修正

Post-Newtonian corrections to the gravitational-wave memory for quasicircular, inspiralling compact binaries

Marc Favata

摘要:

克里斯托杜卢记忆是对引力波场的一种非线性贡献,它来源于引力波应力-能量张量。对于准圆形的,吸气双星,克里斯托杜卢记忆产生了一个不断增长的,非振荡的变化,在引力波的“正”极化,导致永久位移的一对自由下落的测试质量后,波已经通过。除了它的非振荡行为,Christodoulou记忆是有趣的,因为即使它起源于2.5后牛顿(PN)阶多极相互作用,它影响的波形在领先的(牛顿/四极)顺序。这种记忆也可能在双星黑洞合并中被探测到。虽然准圆形的,inspiralling紧凑的双星的引力波偏振的振荡片已计算到3 PN阶,记忆的贡献,偏振只计算到领先的顺序(下一个领先的顺序0.5PN项先前已被证明为零)。本文将准圆吸气双星的记忆计算推广到3 PN阶。虽然存储器的角度依赖性在性质上保持不变,但PN校正项倾向于减小存储器的幅度。给出了度规扰动和曲率扰动对正极化和自旋加权球谐模的记忆贡献的显式表达式。结合Blanchet等人的最新结果,(2008),这完成了3 PN阶的波形。本文还讨论了:(i)从数值模拟中提取记忆的困难,(ii)在高PN阶进入波形的其他非振荡效应,以及(iii)关于记忆的可观测性的问题。

英文摘要:

The Christodoulou memory is a nonlinear contribution to the gravitational-wave field that is sourced by the gravitational-wave stress-energy tensor. For quasicircular, inspiralling binaries, the Christodoulou memory produces a growing, nonoscillatory change in the gravitational-wave "plus" polarization, resulting in the permanent displacement of a pair of freely-falling test masses after the wave has passed. In addition to its nonoscillatory behavior, the Christodoulou memory is interesting because even though it originates from 2.5 post-Newtonian (PN) order multipole interactions, it affects the waveform at leading (Newtonian/quadrupole) order. The memory is also potentially detectable in binary black-hole mergers. While the oscillatory pieces of the gravitational-wave polarizations for quasicircular, inspiralling compact binaries have been computed to 3PN order, the memory contribution to the polarizations has only been calculated to leading order (the next-to-leading order 0.5PN term has previously been shown to vanish). Here the calculation of the memory for quasicircular, inspiralling binaries is extended to 3PN order. While the angular dependence of the memory remains qualitatively unchanged, the PN correction terms tend to reduce the memory's magnitude. Explicit expressions are given for the memory contributions to the plus polarization and the spin-weighted spherical-harmonic modes of the metric and curvature perturbations. Combined with the recent results of Blanchet et al.(2008), this completes the waveform to 3PN order. This paper also discusses: (i) the difficulties in extracting the memory from numerical simulations, (ii) other nonoscillatory effects that enter the waveform at high PN orders, and (iii) issues concerning the observability of the memory.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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