Clash-Vlt: Dissecting the frontier fields galaxy cluster macs j0416. 1-2403 with∼ 800 spectra of member galaxies Academic Article uri icon


  • Abstract We present VIMOS-Very Large Telescope (VLT) spectroscopy of the Frontier Fields cluster MACS J0416. 1-2403 (z= 0.397). Taken as part of the CLASH-VLT survey, the large spectroscopic campaign provided more than 4000 reliable redshifts over~ 600 arcmin 2, including~ 800 cluster member galaxies. The unprecedented sample of cluster members at this redshift allows us to perform a highly detailed dynamical and structural analysis of the cluster out to~ 2.2 r 200 (~ 4 Mpc). Our analysis of substructures reveals a complex system composed of a main massive cluster (M 200~ 0.9× 10 15 M⊙ and σ V, r200~ 1000 km s− 1) presenting two major features:(i) a bimodal velocity distribution, showing two central peaks separated by ΔV rf~ 1100 km s− 1 with comparable galaxy content and velocity dispersion, and (ii) a projected elongation of the main substructures along the NE–SW direction, with …


publication date

  • January 1, 2016