RELICS: Strong Lensing Analysis of the Galaxy Clusters Abell S295, Abell 697, MACS J0025.4-1222, and MACS J0159.8-0849

Abstract

We present a strong-lensing analysis of four massive galaxy clusters imaged with the Hubble Space Telescope in the Reionization Lensing Cluster Survey. We use a Light-Traces-Mass technique to uncover sets of multiply images and constrain the mass distribution of the clusters. These mass models are the first published for Abell S295 and MACS J0159.8-0849, and are improvements over previous models for Abell 697 and MACS J0025.4-1222. Our analysis for MACS J0025.4-1222 and Abell S295 shows a bimodal mass distribution supporting the merger scenarios proposed for these clusters. The updated model for MACS J0025.4-1222 suggests a substantially smaller critical area than previously estimated. For MACS J0159.8-0849 and Abell 697 we find a single peak and relatively regular morphology, revealing fairly relaxed clusters. Despite being less prominent lenses, three of these clusters seem to have lensing strengths, i.e. cumulative area above certain magnification, similar to the Hubble Frontier Fields clusters (e.g., A(µ > 5) ∼ 1 − 3 arcmin 2 , A(µ > 10) ∼ 0.5 − 1.5 arcmin 2 ), which in part can be attributed to their merging configurations. We make our lens models publicly available through the Mikulski Archive for Space Telescopes. Finally, using Gemini-N/GMOS spectroscopic observations we detect a single emission line from a high-redshift J 125 25.7 galaxy candidate lensed by Abell 697. While we cannot rule out a lower-redshift solution, we interpret the line as Lyα at z = 5.800 ± 0.001, in agreement with its photometric redshift and dropout nature. Within this scenario we measure a Lyα rest-frame equivalent width of 52 ± 22Å and an observed Gaussian width of 117 ± 15 km/s.

RELICS: Reionization Lensing Cluster Survey

“…Mahler et al (2018) used spectroscopic redshifts of many arcs from VLT/MUSE (Jauzac et al 2019) to produce a detailed Lenstool model of MACS0417-11, confirming it is a strong lens, despite curiously yielding no z ∼ 6 − 8 candidates (Salmon et al 2017). Cibirka et al (2018) modeled four clusters using the LTM method and presented one lensed galaxy showing strong Lyman-α emission with a spectroscopic redshift z = 5.800. Cerny et al (2018) modeled five clusters using Lenstool and presented detailed estimates of the statistical and systematic uncertainties.…”

Stellar Properties of z ≳ 8 Galaxies in the Reionization Lensing Cluster Survey

“…In order to correct for magnification from lensing, relevant for SFRs and stellar masses, we use lens models created by the RELICS team. We use three lens modeling codes to produce the models for the clusters described (2018), and the LTM models for Abell S295 and PLCKG287+32 are described in detail by Cibirka et al (2018) and Zitrin et al (2017), respectively. The remaining three clusters will have details available in the future, and all models are available on MAST 3 .…”

RELICS: spectroscopy of gravitationally lensed z ≃ 2 reionization-era analogues and implications for C iii] detections at z > 6

“…The magnification provided by the cluster is calculated from lens models prepared by the RELICS team and available to the public. 1 Further details on the lens modeling procedure have been presented in recent RELICS papers (Cerny et al 2018;Paterno-Mahler et al 2018;Cibirka et al 2018;Acebron et al 2018). In calculating the magnification and the absolute magnitude, we assume the confirmed spectroscopic redshift presented in §3.…”