Cosmology with supernova Encore in the strong lensing cluster MACS J0138−2155

作者：S. Ertl, S. H. Suyu, S. Schuldt, G. Granata, C. Grillo, G. B. Caminha, A. Acebron, P. Bergamini, R. Cañameras, Sangjun Cha, J. M. Diego, Nicholas Foo, Brenda Frye, Yoshinobu Fudamoto, A. Halkola, M. James Jee, Patrick S. Kamieneski, Anton M. Koekemoer, Ashish Kumar Meena, S. Nishida, Masamune Oguri, Justin Pierel, P. Rosati, Luca Tortorelli, Han Wang, Adi Zitrin · 发表于：Astronomy and Astrophysics · 年份：2025 · DOI：10.1051/0004-6361/202554477 · 被引用次数：7 · 研究领域：Gamma-ray bursts and supernovae、CCD and CMOS Imaging Sensors、Astronomy and Astrophysical Research

The strongly lensed supernova (SN) Encore, at a redshift of z = 1.949 and discovered behind the galaxy cluster MACS J0138−2155 at z = 0.336, provides a rare opportunity for time-delay cosmography and studies of the SN host galaxy, where previously another SN, called SN Requiem, had appeared. To enable these studies, we combined new James Webb Space Telescope (JWST) imaging, archival Hubble Space Telescope (HST) imaging, and new Very Large Telescope (VLT) spectroscopic data to construct state-of-the-art lens mass models that are composed of cluster dark-matter (DM) haloes and galaxies. We fitted the surface brightness distributions of the galaxies in the field of view using Sérsic profiles to determine their photometric and structural parameters across six JWST and five HST filters. We used the colour-magnitude and colour-colour relations of spectroscopically confirmed cluster members to select additional cluster members, and identified a total of 84 galaxies belonging to the galaxy cluster. We constructed seven different mass models using a variety of DM halo mass profiles and explored both multi-plane and approximate single-plane lens models. As constraints, we used the observed positions of 23 multiple images from eight multiple image systems that originate from four galaxies with distinct spectroscopic redshifts in the range of 0.767–3.420. In addition, we used stellar velocity dispersion measurements to obtain priors on the galaxy mass distributions. We find that six of t...