RELICS: A Strong Lens Model for SPT-CLJ0615-5746, a z = 0.972 Cluster
Abstract
We present a lens model for the cluster SPT-CLJ0615-5746, which is the highest-redshift (z = 0.972) system in the Reionization of Lensing Clusters Survey, making it the highest-redshift cluster for which a full, strong lens model is published. We identify three systems of multiply imaged lensed galaxies, two of which we spectroscopically confirm at z = 1.358 and z = 4.013, which we use as constraints for the model. We find a foreground structure at z ∼ 0.4, which we include as a second cluster-sized halo in one of our models; however, two different statistical tests find the best-fit model consists of one cluster-sized halo combined with three individually optimized galaxy-sized halos, as well as contributions from the cluster galaxies themselves. We find the total projected mass density within r = 26.″7 (the region where the strong lensing constraints exist) to be M={2.51}-0.09+0.15× {10}14 M ⊙. If we extrapolate out to r 500, our projected mass density is consistent with the mass inferred from weak lensing and from the Sunyaev-Zel’dovich effect (M ∼ 1015 M ⊙). This cluster is lensing a previously reported z ∼ 10 galaxy, which, if spectroscopically confirmed, will be the highest-redshift strongly lensed galaxy known.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- August 2018
- DOI:
- 10.3847/1538-4357/aad239
- arXiv:
- arXiv:1805.09834
- Bibcode:
- 2018ApJ...863..154P
- Keywords:
-
- clusters: individual: SPT-CLJ0615–5746;
- gravitational lensing: strong;
- Astrophysics - Astrophysics of Galaxies;
- Astrophysics - Cosmology and Nongalactic Astrophysics
- E-Print:
- 15 pages, 8 figures 4 tables. ApJ Accepted