Prospects for the VH(cc) search at HL-LHC

The expected sensitivity of a search for decays of the Higgs boson into charm quarks is estimated for the ATLAS detector at the HL-LHC, by extrapolating the results obtained using a dataset with an integrated luminosity of $36.1\ \text{fb}^{-1}$ at $\sqrt{s}=13\ \text{TeV}$. Associated production of Higgs and $Z$ bosons is targeted, where the $Z$ bosons decay to electrons or muons. Assuming an integrated luminosity of $3000\ \text{fb}^{-1}$ of $pp$ collision data at $\sqrt{s}=14\ \text{TeV}$, an expected $95\%\ CL_s$ upper limit of $6.3\times$ the Standard Model expectation for $\sigma(pp\rightarrow ZH)\times{\cal B}(H\rightarrow c\bar c)$ is estimated, in the absence of systematic uncertainties. The impact of systematic uncertainties and possible improvements in the flavour tagging performance on the sensitivity are estimated.