Weak lensing analysis of RXC J2248.7-4431
  We present a weak lensing analysis of the cluster of galaxies RXC
J2248.7-4431, a massive system at z=0.3475 with prominent strong lensing
features covered by the HST/CLASH survey (Postman et al. 2012). Based on UBVRIZ
imaging from the WFI camera at the MPG/ESO-2.2m telescope, we measure
photometric redshifts and shapes of background galaxies. The cluster is
detected as a mass peak at 5sigma significance. Its density can be parametrised
as an NFW profile (Navarro et al. 1996) with two free parameters, the mass
M_200m=(33.1+9.6-6.8)x10^14Msol and concentration c_200m=2.6+1.5-1.0. We
discover a second cluster inside the field of view at a photometric redshift of
z~0.6, with an NFW mass of M_200m=(4.0+3.7-2.6)x10^14Msol.
