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arXiv · 1805.09834

RELICS: A Strong Lens Model for SPT-CLJ0615-5746, a z=0.972 Cluster

Rachel Paterno-Mahler·Keren Sharon·Dan Coe·Guillaume Mahler·Catherine Cerny·Traci Johnson·Tim Schrabback·Felipe Andrade-Santos·Roberto J. Avila·Marusa Bradac·Larry D. Bradley·Daniela Carrasco·Nicole G. Czakon·William A. Dawson·Brenda L. Frye·Austin T. Hoag·Kuang-Han Huang·Christine Jones·Daniel Lam·Rachael Livermore·Lorenzo Lovisari·Ramesh Mainali·Pascal A. Oesch·Sara Ogaz·Matthew Past·Avery Peterson·Russell E. Ryan·Brett Salmon·Irene Sendra-Server·Daniel P. Stark·Keiichi Umetsu·Benedetta Vulcani·Adi Zitrin
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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 (RELICS), 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 $z\sim0.4$, 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 $M=2.51^{+0.15}_{-0.09}\times 10^{14}$~M$_{\odot}$. 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 ($M\sim10^{15}$~M$_{\odot}$). This cluster is lensing a previously reported $z\sim10$ galaxy, which, if spectroscopically confirmed, will be the highest-redshift strongly lensed galaxy known.

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Rachel Paterno-Mahler, Keren Sharon, Dan Coe, Guillaume Mahler, Catherine Cerny, Traci Johnson, Tim Schrabback, Felipe Andrade-Santos, Roberto J. Avila, Marusa Bradac, Larry D. Bradley, Daniela Carrasco, Nicole G. Czakon, William A. Dawson, Brenda L. Frye, Austin T. Hoag, Kuang-Han Huang, Christine Jones, Daniel Lam, Rachael Livermore, Lorenzo Lovisari, Ramesh Mainali, Pascal A. Oesch, Sara Ogaz, Matthew Past, Avery Peterson, Russell E. Ryan, Brett Salmon, Irene Sendra-Server, Daniel P. Stark, Keiichi Umetsu, Benedetta Vulcani, Adi Zitrin. 2018-05-24. RELICS: A Strong Lens Model for SPT-CLJ0615-5746, a z=0.972 Cluster. https://doi.org/10.3847/1538-4357%2Faad239

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