Strongly Lensed Supernovae in Well-Studied Galaxy Clusters with the Vera C. Rubin Observatory

Tanja Petrushevska

doi:10.3390/sym12121966

Abstract

Strong lensing by galaxy clusters can be used to significantly expand the survey reach, thus allowing observation of magnified high-redshift supernovae that otherwise would remain undetected. Strong lensing can also provide multiple images of the galaxies that lie behind the clusters. Detection of strongly lensed Type Ia supernovae (SNe Ia) is especially useful because of their standardizable brightness, as they can be used to improve either cluster lensing models or independent measurements of cosmological parameters. The cosmological parameter, the Hubble constant, is of particular interest given the discrepancy regarding its value from measurements with different approaches. Here, we explore the feasibility of the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST) of detecting strongly lensed SNe in the field of five galaxy clusters (Abell 1689 and Hubble Frontier Fields clusters) that have well-studied lensing models. Considering the 88 systems composed of 268 individual multiple images in the five cluster fields, we find that the LSST will be sensitive to SNe Ia (SNe IIP) exploding in 41 (23) galaxy images. The range of redshift of these galaxies is between 1.01<z<3.05. During its 10 years of operation, LSST is expected to detect 0.2±0.1 SN Ia and 0.9±0.3 core collapse SNe. However, as LSST will observe many more massive galaxy clusters, it is likely that the expectations are higher. We stress the importance of having an additional observing program for photometric and spectroscopic follow-up of the strongly lensed SNe detected by LSST.

Highlights

Supernovae (SNe) have proved to be invaluable tools for various astrophysical and cosmological applications
Considering the five well-studied galaxy clusters and their background strongly lensed galaxies with multiple images, we find that the Legacy Survey of Space and Time (LSST) will be sensitive to SNe Type Ia (SNe Ia) exploding in 41 galaxies, while for the most common CC SNe, SNe IIP, the number is lower, 23
SNe IIP are visible to LSST at higher redshifts because they emit much more in the rest-frame UV, so at high redshift that region is shifted and it is still visible with the LSST filters at the longest wavelengths

Summary

Introduction

Supernovae (SNe) have proved to be invaluable tools for various astrophysical and cosmological applications. As the images have taken different paths through space before reaching us, the time differences between the images are sensitive to the expansion rate of the universe, parametrized by the Hubble constant, H0 [2]. These time delays are sensitive to other cosmological parameters, albeit to a much lesser extent [3]. The time delays depend on the lensing potential; strongly lensed SNe can be used for both cosmological and cluster lens studies [5,6,7,8]

Results

Discussion

Conclusion