MUSE spectroscopy and deep observations of a unique compact JWST target, lensing cluster CLIO
Abstract
We present the results of a VLT MUSE/FORS2 and Spitzer survey of a unique compact lensing cluster CLIO at z = 0.42, discovered through the GAMA survey using spectroscopic redshifts. Compact and massive clusters such as this are understudied, but provide a unique prospective on dark matter distributions and for finding background lensed high-z galaxies. The CLIO cluster was identified for follow-up observations due to its almost unique combination of high-mass and dark matter halo concentration, as well as having observed lensing arcs from ground-based images. Using dual band optical and infra-red imaging from FORS2 and Spitzer, in combination with MUSE optical spectroscopy we identify 89 cluster members and find background sources out to z = 6.49. We describe the physical state of this cluster, finding a strong correlation between environment and galaxy spectral type. Under the assumption of an NFW profile, we measure the total mass of CLIO to be M200 = (4.49 ± 0.25) × 1014 M⊙. We build and present an initial strong-lensing model for this cluster, and measure a relatively low intracluster light (ICL) fraction of 7.21 ± 1.53 per cent through galaxy profile fitting. Due to its strong potential for lensing background galaxies and its low ICL, the CLIO cluster will be a target for our 110 h James Webb Space Telescope `Webb Medium-Deep Field' (WMDF) GTO program.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- April 2018
- DOI:
- 10.1093/mnras/stx3364
- arXiv:
- arXiv:1801.01140
- Bibcode:
- 2018MNRAS.475.2853G
- Keywords:
-
- gravitational lensing: strong;
- techniques: imaging spectroscopy;
- galaxies: clusters: general;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- Accepted at MNRAS, 19 pages, 16 figures