Search for the Standard Model Higgs boson in the vector boson fusion-mediated diphoton decay channel using multivariate analysis techniques

A search for the Standard Model Higgs boson in the diphoton decay channel is presented using multivariate analysis techniques, with a focus on the vector boson fusion (VBF) production mechanism. Data events are separated into signal (VBF Hyy) and background-like categories using a gradient boosted decision tree, with the optimized analysis applied to the full 2011-2012 dataset, corresponding to 4.8 fb-1 of sqrt(s) = 7 TeV pp collisions, and 21 fb-1 of sqrt(s) = 8 TeV collisions. The best fit invariant mass for events categorized as VBF Hyy is found to be mH = 123.5 GeV, with a local significance of 2.9 sigma. The best fit signal strength for the W, Z-mediated Hyy decay (VBF + associated production) is found to be mu = 1.72, which agrees with Standard Model predictions within 2 sigma.