用星系团透镜引力波时间延迟探测修正引力：系统效应的影响
Probing modified gravity with galaxy-cluster-lensed gravitational-wave time delays: impact of systematic effects
- Imperial College（帝国理工学院）
- Observatoire de Paris, Université PSL, Sorbonne Université, CNRS（巴黎天文台，巴黎文理研究大学，索邦大学，法国国家科学研究中心）
- Alma Mater Studiorum Universita di Bologna（博洛尼亚大学）
- INAF - Osservatorio di Astrofisica e Scienza dello Spazio di Bologna（意大利国家天体物理研究所博洛尼亚天文与空间科学观测站）
- INFN - Sezione di Bologna（意大利国家核物理研究所博洛尼亚分部）
机构由 AI 辅助整理，请以论文原文为准。
中文总结 AI 辅助
本文提出概念验证流程，用模拟双中子星源经星系团透镜的时间延迟跨度约束Weyl势修正参数D，发现忽略晕椭率等系统效应会引入显著偏差，需显式处理才能作为精密引力测试。
中文摘要 AI 辅助
强透镜引力波能够提供对宏观像相对到达时间的极其精确的测量，使其时间延迟成为星系团尺度上引力的一个有前景的时域探针。这种精度对透镜系统效应的控制提出了严格要求。我们提出了一个概念验证流程，用于约束星系团Weyl势的唯象修正$D$，该流程使用模拟的双中子星（BNS）源样本和由Navarro-Frenk-White团晕及最亮星系团星系（BCG）的奇异等温球描述的团透镜的宏观像时间延迟跨度。闭合测试恢复了注入的广义相对论（GR）极限。采用重建时间延迟跨度的5%基准精度，我们评估了团晕质量和浓度、BCG贡献、源和透镜位置、红移、视线环境、投影椭率和次级团尺度结构的受控错误设定。在所采用的引力模型内，忽略晕椭率、次级团尺度结构、团错心和视线扰动可导致推断参数$D$的显著且强烈依赖构型的偏差。团晕质量和浓度的有偏估计，以及所考虑水平上的系统BNS源位置误差，产生显著的相干偏移。相比之下，BCG贡献以及透镜和源红移的不确定性相对次要。这些结果强调，在团透镜引力波时间延迟可用作引力的精确测试之前，需要明确处理上述不确定性。
英文摘要
Strongly lensed gravitational waves provide exceptionally precise measurements of relative macroimage arrival times, making their time delays a promising time-domain probe of gravity on galaxy-cluster scales. This precision places stringent demands on the control of lensing systematic effects. We present a proof-of-concept pipeline for constraining a phenomenological modification, $D$, of the galaxy cluster Weyl potential using the macroimage time-delay span of a simulated sample of binary neutron star (BNS) sources and cluster lenses described by a Navarro--Frenk--White cluster halo and a singular isothermal sphere for the brightest cluster galaxy (BCG). Closure tests recover the injected general-relativistic (GR) limit. Adopting a fiducial 5 per cent precision on the reconstructed time-delay span, we assess controlled mis-specifications of the halo mass and concentration, BCG contribution, source and lens positions, redshifts, line-of-sight environment, projected ellipticity and secondary cluster-scale structure. Within the adopted gravity model, neglecting halo ellipticity, secondary cluster-scale structure, cluster mis-centring and line-of-sight perturbations can induce significant, strongly configuration-dependent biases in the inferred parameter $D$. Biased estimates of the cluster halo mass and concentration, as well as systematic BNS source-position errors at the level considered here, produce significant coherent shifts. By contrast, uncertainties in the BCG contribution and in the lens and source redshifts are comparatively subdominant. These results highlight the need for explicit treatment of the above uncertainties before cluster-lensed gravitational wave time delays can be used as precision tests of gravity.
