Search for the Decay of the Higgs Boson to Charm Quarks with the ATLAS Experiment

A direct search for the standard model Higgs boson decaying to a pair of charm quarks is presented. Associated production of the Higgs and Z bosons, in the decay mode ZH → lþl−cc¯ is studied. A data set with an integrated luminosity of 36.1 fb−1 of pp collisions at ffiffi s p ¼ 13TeV recorded by the ATLAS experiment at the LHC is used. The H → cc¯ signature is identified using charm-tagging algorithms. The observed (expected) upper limit on σðpp → ZHÞ × BðH → cc¯Þ is 2.7 (3.9þ2.1 −1.1 ) pb at the 95% confidence level for a Higgs boson mass of 125 GeV, while the standard model value is 26 fb.