Search for $H^0 \rightarrow b \bar{b}$ or $c \bar{c}$ in association with a $W$ or $Z$ boson in the forward region of $pp$ collisions

The LHCb dataset consisting of proton--proton collisions recorded at $\sqrt{s}=8$ $\mathrm{TeV}$, corresponding to an integrated luminosity of 1.98 $\pm$ 0.02 $fb^{-1}$, is used to search for a Higgs boson with a mass of 125 $\mathrm{GeV}$, produced in association with a $W$ or $Z$ boson and decaying to a $b \bar{b}$ or $c \bar{c}$ pair. The final state considered is a pair of heavy flavour tagged jets and one or two high $p_T$ leptons (electrons or muons). No excess over the background expectation is found and upper limits on the product of cross section times branching fraction, with two heavy quarks from $H^0$ and one lepton from $W$/$Z$ in the $\text {LHCb}$ acceptance $2 < \eta < 5$, are set at $95\% ~\text{CL}$: \begin{align} \sigma (pp \rightarrow W/Z + H^0 ) \times \mathrm{{\cal B}}(H^0 \to b \bar{b}) < 1.6 ~ \mathrm{pb}, \end{align} \begin{align} \sigma(pp \rightarrow W/Z + H^0 ) \times \mathrm{{\cal B}}(H^0 \to c \bar{c}) < 9.4 ~ \mathrm{pb}. \end{align}