TDCOSMO: XII. Improved Hubble constant measurement from lensing time delays using spatially resolved stellar kinematics of the lens galaxy
TDCOSMO: XII. Improved Hubble constant measurement from lensing time delays using spatially resolved stellar kinematics of the lens galaxy
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TDCOSMO：十二。
DOI：
10.1051/0004-6361/202345878
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发表时间：
2023
影响因子：
6.5
通讯作者：
Sluse, Dominique
中科院分区：
文献类型：
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作者：
Shajib, Anowar J.;Mozumdar, Pritom;Chen, Geoff C.-F.;Treu, Tommaso;Cappellari, Michele;Knabel, Shawn;Suyu, Sherry H.;Bennert, Vardha N.;Frieman, Joshua A.;Sluse, Dominique
强透镜时间延迟使哈勃常数（H 0）的测量独立于其他传统方法。质量片简并度是制约时延天体照相精度的主要因素。TDCOSMO之前的一些分析通过对透镜星系的质量密度分布做出标准假设，打破了MSD，通过7个透镜达到了2%的精度。然而，这种方法可能会使H 0测量产生偏差或低估误差。在这项工作中，我们第一次打破了MSD，使用从Keck宇宙网成像仪光谱获得的RXJ 1131 −1231中透镜星系的空间分辨运动学，结合先前发表的时间延迟和从哈勃太空望远镜成像中获得的透镜模型。这种方法使我们能够稳健地估计H 0，有效地实现了最大灵活的质量模型。在盲分析之后，我们估计了到透镜星系的角直径距离Mpc和时间延迟距离Mpc，给出了平坦Λ冷暗物质宇宙学的km s− 1 Mpc −1-。误差预算考虑了所有的不确定性，包括透镜质量分布和视线效应所固有的MSD，以及与质量各向异性简并和投影效应相关的MSD。我们的新测量与过去使用标准简单参数化质量分布获得的结果非常一致，对于这个单一系统（km s− 1 Mpc −1）和七个透镜（km s− 1 Mpc −1），或者使用单孔径运动学和我们使用的相同最大柔性模型（km s− 1 Mpc −1）的七个透镜。这一协议证实了时间延迟宇宙学的方法。
Strong-lensing time delays enable the measurement of the Hubble constant (H0) independently of other traditional methods. The main limitation to the precision of time-delay cosmography is mass-sheet degeneracy (MSD). Some of the previous TDCOSMO analyses broke the MSD by making standard assumptions about the mass density profile of the lens galaxy, reaching 2% precision from seven lenses. However, this approach could potentially bias theH0measurement or underestimate the errors. For this work, we broke the MSD for the first time using spatially resolved kinematics of the lens galaxy in RXJ1131−1231 obtained from the Keck Cosmic Web Imager spectroscopy, in combination with previously published time delay and lens models derived fromHubbleSpace Telescope imaging. This approach allowed us to robustly estimateH0, effectively implementing a maximally flexible mass model. Following a blind analysis, we estimated the angular diameter distance to the lens galaxy Mpc and the time-delay distance Mpc, giving km s−1Mpc−1– for a flat Λ cold dark matter cosmology. The error budget accounts for all uncertainties, including the MSD inherent to the lens mass profile and line-of-sight effects, and those related to the mass–anisotropy degeneracy and projection effects. Our new measurement is in excellent agreement with those obtained in the past using standard simply parametrized mass profiles for this single system ( km s−1Mpc−1) and for seven lenses ( km s−1Mpc−1), or for seven lenses using single-aperture kinematics and the same maximally flexible models used by us ( km s−1Mpc−1). This agreement corroborates the methodology of time-delay cosmography.