发表机构
University of California, Davis（加州大学戴维斯分校）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究探讨利用光学光谱探测引力透镜移动效应，以并合星系团为案例，发现该测量可区分不同并合模型。
AI 中文摘要
相对论预言，引力透镜在天空平面上的运动会改变被透镜化光子的波长。这种移动透镜效应比同一光子上宇宙学和多普勒效应小若干个数量级，但可以通过比较给定源的不同强透镜图像来分离出来。对于一个质量巨大且快速移动的透镜，例如正在落入另一个星系团的星系团，给定源的透镜化光谱在波长上可能相差高达百万分之一。我们以并合星系团RM J001938.7+033557.3的Keck/Deimos数据为案例研究，考察了利用光学光谱探测该效应的可行性。我们还量化了在ΛCDM宇宙学中可能被识别为并合星系团的系统的预期天空平面运动，并研究了天空平面运动信息如何有助于约束并合模型。我们发现，测量移动透镜效应将能区分子星系团在首次近心点后向外运动与子星系团在首次远心点后回到相同间距的模型。
英文摘要
Relativity predicts that sky-plane motion of a gravitational lens changes the wavelengths of lensed photons. This moving lens effect is orders of magnitude smaller than cosmological and Doppler effects on the same photons, but can be isolated by comparing different strongly lensed images of a given source. With a massive, fast-moving lens such as a galaxy cluster falling into another cluster, lensed spectra of a given source could differ in wavelength by up to 1 part in $10^6$. We examine the feasibility of detecting this effect with optical spectroscopy, using Keck/Deimos data on the merging cluster RM J001938.7+033557.3 as a case study. We also quantify the predicted sky-plane motions of systems likely to be identified as merging clusters in a $Λ$CDM cosmology, and investigate how information on sky-plane motions could help constrain merger models. We find that measurement of the moving lens effect would disambiguate between models in which the subclusters are outbound after first pericenter and those in which the subclusters have returned to the same separation after first apocenter.
Commentssubmitted to ApJ
