Searching for a light Higgs boson via the Yukawa process at lepton colliders

Abstract

We explore the prospect of Yukawa production of a light boson which can exist in an extended Higgs sector. A particularly interesting case is the light pseudoscalar in Type-X two Higgs doublet model which can explain the anomalous magnetic moment of muon at large . Considering ILC Higgs factory with GeV, we show that the available parameter space can be fully examined by the (tau) Yukawa process at 5σ. We also demonstrate the mass reconstruction of such a light particle which helps to sizably minimize the background events.