Diphoton production in the ADD model to NLO+parton shower accuracy at   the LHC
  In this paper, we present the next-to-leading order predictions for diphoton production in the ADD model, matched to the HERWIG parton shower using the MC@NLO formalism. A selection of the results is presented for d=2-6 extra dimensions, using generic cuts as well as analysis cuts mimicking the search strategies as pursued by the ATLAS and CMS experiments. 
R. Frederix, Manoj K. Mandal, Prakash Mathews, V. Ravindran, Satyajit   Seth, P. Torrielli, M. Zaro
hep-ph hep-ex