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Abstract: I will present our current efforts to enable the use of strongly lensed supernovae behind galaxy clusters as powerful tools to tackle several open questions in astrophysics and cosmology. As a preparatory task, we are collecting all available gravitational telescopes into a database, and estimating the properties of all reported multiply-imaged galaxies behind clusters. We are building a tool that will enable accurate estimates of cluster-lensed supernova yields for a given survey. In addition, we are developing the methods to extract the cosmological parameters from cluster-lensed supernovae in the Rubin and Roman data.
Keywords: supernova, gravitational lensing, Vera Rubin Observatory, Roman Space telescope, LSST, Hubble constant
Published in RUNG: 09.11.2022; Views: 1018; Downloads: 5
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Abstract: Aims. We present a ground-based, near-infrared search for lensed supernovae behind the massive cluster Abell 1689 at z = 0.18, which is one of the most powerful gravitational telescopes that nature provides. Methods. Our survey was based on multi-epoch J-band observations with the HAWK-I instrument on VLT, with supporting optical data from the Nordic Optical Telescope. Results. Our search resulted in the discovery of five photometrically classified, core-collapse supernovae with high redshifts of 0.671 < z < 1.703 and magnifications in the range ∆m = −0.31 to −1.58 mag, as calculated from lensing models in the literature. Owing to the power of the lensing cluster, the survey had the sensitivity to detect supernovae up to very high redshifts, z ∼ 3, albeit for a limited region of space. We present a study of the core-collapse supernova rates for 0.4 ≤ z < 2.9, and find good agreement with previous estimates and predictions from star formation history. During our survey, we also discovered two Type Ia supernovae in A 1689 cluster members, which allowed us to determine the cluster Ia rate to be 0.14+0.19 ± 0.01 SNuB h2 (SNuB ≡ −0.09 10−12 SNe L−1 yr−1 ), where the error bars indicate 1σ confidence intervals, statistical and systematic, respectively. The cluster rate ⊙,B normalized by the stellar mass is 0.10+0.13 ± 0.02 in SNuM h2 (SNuM ≡ 10−12 SNe M−1 yr−1). Furthermore, we explore the optimal −0.06 ⊙ future survey for improving the core-collapse supernova rate measurements at z 2 using gravitational telescopes, and for detections with multiply lensed images, and we find that the planned WFIRST space mission has excellent prospects. Conclusions. Massive clusters can be used as gravitational telescopes to significantly expand the survey range of supernova searches, with important implications for the study of the high-z transient Universe.
Keywords: supernova, gravitational telescope, galaxy clusters, Abell 1689, strong lensing
Published in RUNG: 26.01.2018; Views: 3332; Downloads: 0
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