Isolating a light Higgs boson from the diphoton background at the CERN LHC

We compute the QCD corrections to the gluon fusion subprocess gg-->gammagamma, which forms an important component of the background to the search for a light Higgs boson at the CERN LHC. We study the dependence of the improved pp-->gammagammaX background calculation on the factorization and renormalization scales, on various choices for photon isolation cuts, and on the rapidities of the photons. We also investigate ways to enhance the statistical significance of the Higgs signal in the gammagamma channel.