Abstract

Decays of the Higgs boson to exclusive final states involving light hadrons or quarkonia have recently received much attention due to their sensitivity to the first and second generation quark Yukawa couplings. In the particular, the decay of the Higgs to a J/psi and photon has been suggested as clean way to measure the charm Yukawa coupling at the LHC, a quantity which is difficult to measure in inclusive Higgs decays to charm quarks. The analogous decay of the Z boson can also serve as a useful control channel to this measurement and benefits from a much greater experimental sensitivity due to the much larger relative production cross section. I will describe the first search for Higgs and Z boson decays to a quarkonium state and a photon with the ATLAS experiment and will also discuss the prospects for such searches with larger data samples at higher energies.