MUSE observations of the lensing cluster SMACSJ2031.8-4036: new constraints on the mass distribution in the cluster core

Johan Richard (1) , Vera Patricio (1) , Johany Martinez (1) , Roland Bacon (1) , Benjamin Clément (1) , Peter Weilbacher (2) , Kurt Soto (3) , Lutz Wisotzki (2) , Joël Vernet (4) , Roser Pello (5) , Joop Schaye (6) , Monica Turner (6) , Thomas Martinsson (6)

1 CRAL - Centre de Recherche Astrophysique de Lyon
2 AIP - Astrophysikalisches Institut Potsdam
3 ETH Zürich - Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich]
4 ESO - European Southern Observatory
5 IRAP - Institut de recherche en astrophysique et planétologie
6 Leiden Observatory [Leiden]

We present new observations of the lensing cluster SMACSJ2031.8-4036 obtained with the Multi Unit Spectroscopic Explorer (MUSE) integral field spectrograph as part of its commis-sioning on the Very Large Telescope. By providing medium-resolution spectroscopy over the full 4750–9350 Å domain and a 1 × 1 arcmin 2 field of view, MUSE is ideally suited for iden-tifying lensed galaxies in the cluster core, in particular multiple-imaged systems. We perform a redshift analysis of all sources in the data cube and identify a total of 12 systems ranging from z = 1.46 to 6.4, with all images of each system confirmed by a spectroscopic redshift. This allows us to accurately constrain the cluster mass profile in this region. We foresee that future MUSE observations of cluster cores should help us discover very faint Lyman α emitters thanks to the strong magnification and the high sensitivity of this instrument.

Domaines: Cosmologie et astrophysique extra-galactique [astro-ph.CO]

Johan Richard, Vera Patricio, Johany Martinez, Roland Bacon, Benjamin Clément, et al.. MUSE observations of the lensing cluster SMACSJ2031.8-4036: new constraints on the mass distribution in the cluster core. Monthly Notices of the Royal Astronomical Society, 2015, 446, pp.16 - 20. ⟨10.1093/mnrasl/slu150⟩. ⟨hal-01109664v2⟩