Hosted by: Ketevi A. Assamagan

The dark photon, A′,, and the dark Higgs boson, h′, are hypothetical constituents featured in a number of recently proposed Dark Sector Models. We will present a search for these particles in the so-called Higgs-strahlung channel, e+eâˆ'â†'A′h′, with h′â†'A′A′. We investigated ten exclusive final-states with A′â†'e+eâˆ', μ+μâˆ', or Ï€+Ï€âˆ', in the mass ranges 0.1 GeV/c2 <mA′<3.5 GeV/c2 and 0.2 GeV/c2 <mh′<10.5 GeV/c2. We also investigated three inclusive final-states, 2(e+eâˆ')X, 2(μ+μâˆ')X, and (e+eâˆ')(μ+μâˆ')X, where X denotes a dark photon candidate detected via missing mass, in the mass ranges 1.1 GeV/c2 <mA′<3.5 GeV/c2 and 2.2 GeV/c2 <mh′<10.5 GeV/c2. Using the entire 977fbâˆ'1 data set collected by Belle, we observed no significant signal. We will also discuss prospects for searches for light dark matter and the dark photon in the radiative decay process at Belle and Belle II.