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 $ZH\rightarrow \cal{l}^{+} \cal{l}^{-} c \bar{c}$ is studied. A dataset with an integrated luminosity of $36.1\,\text{fb}^{-1}$ of $pp$ collisions at $\sqrt{s}=13\,\text{TeV}$ recorded by the ATLAS experiment at the LHC is used. The $H\rightarrow c\bar{c}$ signature is identified using charm tagging algorithms. The observed (expected) upper limit on $\sigma(pp \rightarrow ZH) \times \mathcal{B}(H \rightarrow c\bar{c})$ is $2.7\,(3.9^{+2.1}_{-1.1})\,\text{pb}$ at the 95% confidence level for a Higgs boson mass of $125\,\text{GeV}$, while the Standard Model value is $25.5\,\text{fb}$.