致密双星的准5.5 PN TaylorF2近似：质点定相和对潮汐极化率推断的影响
Quasi-5.5PN TaylorF2 approximant for compact binaries: point-mass phasing and impact on the tidal polarizability inference
摘要：
我们推导出一个质点（nonspinning）频域泰勒F2相位近似在准5.5后牛顿（PN）的引力波从合并紧凑的双星精度。新的近似是通过将有效单体（EOB）的能量和角动量通量沿圆轨道进行泰勒展开得到的，其中所有已知的测试粒子信息达到5.5PN。在4PN阶和超越进入能量通量和能量的-尚未计算-项被考虑为自由参数，然后设置为零。我们比较准5.5 PN和3.5 PN近似对全EOB波形使用规范不变的相位诊断$Q_ω=\hatω^2/\dot{\hatω}$，其中$\hatω$是无量纲引力波频率。准5.5PN的相位被发现是系统更接近EOB一个比3.5PN的。值得注意的是，准5.5 PN（3.5 PN）近似累积的EOB $-$ PN相移$ΔΨ^{\rm EOBPN}\sim10^{-3}$ rad（$0.13$ rad）的频率$\hatω\simeq 0.06$，6轨道合并，（$\hatω\simeq 0.086$，2轨道合并）的基准双星中子星系统。我们探讨了准5.5 PN近似的性能上的测量潮汐极化率参数$\tildeΛ$使用注入的EOB波形与数值相对论合并波形杂交。我们证明，准5.5 PN质点近似增强与6 PN准确的潮汐条款允许一个减少（在许多情况下，甚至消除）的偏差，而不是发现$\tildeΛ$的测量时，使用标准的3.5 PN质点基线。在方法上，我们证明了结合使用$Q_ω$分析和贝叶斯参数估计提供了一个新的工具来调查引力波推断的系统学的影响。
英文摘要：
We derive a point-mass (nonspinning) frequency-domain TaylorF2 phasing approximant at quasi-5.5 post-Newtonian (PN) accuracy for the gravitational wave from coalescing compact binaries. The new approximant is obtained by Taylor-expanding the effective-one-body (EOB) resummed energy and and angular momentum flux along circular orbits with all the known test-particle information up to 5.5PN. The -- yet uncalculated -- terms at 4PN order and beyond entering both the energy flux and the energy are taken into account as free parameters and then set to zero. We compare the quasi-5.5PN and 3.5PN approximants against full EOB waveforms using gauge-invariant phasing diagnostics $Q_ω=\hatω^2/\dot{\hatω}$, where $\hatω$ is the dimensionless gravitational-wave frequency. The quasi-5.5PN phasing is found to be systematically closer to the EOB one than the 3.5PN one. Notably, the quasi-5.5PN (3.5PN) approximant accumulates a EOB$-$PN dephasing of $ΔΨ^{\rm EOBPN}\sim10^{-3}$rad ($0.13$rad) up to frequency $\hatω\simeq 0.06$, 6 orbits to merger, ($\hatω\simeq 0.086$, 2 orbits to merger) for a fiducial binary neutron star system. We explore the performance of the quasi-5.5PN approximant on the measurement of the tidal polarizability parameter $\tildeΛ$ using injections of EOB waveforms hybridized with numerical relativity merger waveforms. We prove that the quasi-5.5PN point-mass approximant augmented with 6PN-accurate tidal terms allows one to reduce (and in many cases even eliminate) the biases in the measurement of $\tildeΛ$ that are instead found when the standard 3.5PN point-mass baseline is used. Methodologically, we demonstrate that the combined use of $Q_ω$ analysis and of the Bayesian parameter estimation offers a new tool to investigate the impact of systematics on gravitational-wave inference.
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。
