Projection of searches for exotic Higgs boson decays to light pseudoscalars for the High-Luminosity LHC

This Physics Analysis Summary details the projections of two searches for exotic decays of the Higgs boson from LHC Run 2 to the High-Luminosity LHC. Decays to a pair of light pseudoscalar bosons are explored, in the final states of two $\tau$ leptons and two muons, or two $\tau$ leptons and two b quarks. The projections are based on analyses that use 35.9 fb$^{-1}$ proton-proton collision data recorded at a center-of-mass energy of 13 TeV in 2016. Integrated luminosities of up to 3000 fb$^{-1}$ are considered in the projections, with different scenarios for the extrapolation of the systematic uncertainties.