  We derive the stellar mass fraction in the galaxy cluster RXC J2248.7-4431
observed with the Dark Energy Survey (DES) during the Science Verification
period. We compare the stellar mass results from DES (five filters) with those
from the Hubble Space Telescope Cluster Lensing And Supernova Survey (CLASH; 17
filters). When the cluster spectroscopic redshift is assumed, we show that
stellar masses from DES can be estimated within 25% of CLASH values. We compute
the stellar mass contribution coming from red and blue galaxies, and study the
relation between stellar mass and the underlying dark matter using weak lensing
studies with DES and CLASH. An analysis of the radial profiles of the DES total
and stellar mass yields a stellar-to-total fraction of f*=(6.8+-1.7)x10^-3
within a radius of r_200c~2 Mpc. Our analysis also includes a comparison of
photometric redshifts and star/galaxy separation efficiency for both data sets.
We conclude that space-based small field imaging can be used to calibrate the
galaxy properties in DES for the much wider field of view. The technique
developed to derive the stellar mass fraction in galaxy clusters can be applied
to the ~100 000 clusters that will be observed within this survey and yield
important information about galaxy evolution.
