Evidence for a narrow Higgs-like diphoton resonance with a mass of 125 GeV in pp collisions at [square root of]s = 7 - 8 TeV

Abstract

We have performed a search for the production of the standard model Higgs boson decaying to diphotons in pp collisions at the LHC at [square root of]s = 7-8 TeV with the CMS detector. Having analyzed data corresponding to 5.1 fb-1 at [square root of]s = 7 TeV (2011) and 5.3 fb-1 at [square root of]s = 8 TeV (2012), a statistically significant excess of events is observed with respect to the background prediction. Interpreted as a standard model Higgs, this excess has a local significance of 4.1 standard deviations, with the maximum significance occurring for a Higgs mass of 125 GeV. Taking into account the trials factor given the search range of 110 GeV to 150 GeV in Higgs mass, this excess has a global significance of 3.2 standard deviations. This constitutes evidence for a new particle decaying to diphotons with a mass of around 125 GeV. The rate of observed events is consistent with predictions for the standard model Higgs boson.