  The differential cross sections for the production of photons in Z to mu+ mu-
gamma decays are presented as a function of the transverse energy of the photon
and its separation from the nearest muon. The data for these measurements were
collected with the CMS detector and correspond to an integrated luminosity of
4.7 inverse femtobarns of pp collisions at sqrt(s) = 7 TeV delivered by the
CERN LHC. The cross sections are compared to simulations with POWHEG and
PYTHIA, where PYTHIA is used to simulate parton showers and final-state
photons. These simulations match the data to better than 5%.
