Searching for the Wγ decay of a charged Higgs boson

Abstract We study the prospects for charged Higgs boson searches in the Wγ decay channel. This loop-induced decay channel can be important if the charged Higgs is fermiophobic, particularly when its mass is below the WZ threshold. We identify useful kinematic observables and evaluate the future Large Hadron Collider sensitivity to this channel using the custodial-fiveplet charged Higgs in the Georgi-Machacek model as a fermiophobic benchmark. We show that the LHC with 300 fb−1 of data at 14 TeV will be able to exclude charged Higgs masses below about 130 GeV for almost any value of the SU(2) L -triplet vacuum expectation value in the model, and masses up to 200 GeV and beyond when the triplet vacuum expectation value is very small. We describe the signal simulation tools created for this analysis, which have been made publicly available.