  Results are presented from a search for new physics in final states
containing a photon and missing transverse momentum. The data correspond to an
integrated luminosity of 19.6 inverse femtobarns collected in proton-proton
collisions at sqrt(s) = 8 TeV with the CMS experiment at the CERN LHC. No
deviation from the standard model predictions is observed for these final
states. New, improved limits are set on dark matter production and on
parameters of models with large extra dimensions. In particular, the first
limits from the LHC on branon production are found and significantly extend
previous limits from LEP and the Tevatron. An upper limit of 14.0 fb on the
cross section is set at the 95% confidence level for events with a monophoton
final state with photon transverse momentum greater than 145 GeV and missing
transverse momentum greater than 140 GeV.
