Searching for Charged Higgs Bosons via e + e − → H + H − → c ¯ b c ¯ b $$ \overline{c}b\overline{c}b $$ at Linear Colliders

Abstract

Abstract We study a search for the charged Higgs boson via e + e − → H + H − → c ¯ b c ¯ b $$ \overline{c}b\overline{c}b $$ at the 500 GeV ILC. In a general two Higgs doublet model without Z 2 symmetry, extra Yukawa couplings ρ tt and ρ tc can drive baryogenesis, but searches at the HL-LHC may still go empty-handed if the couplings are relatively weak. Taking m H + $$ {m}_{H^{+}} $$ ≃ m H ≃ m A ≃ 200 GeV, with ρ tt , ρ tc ∼ 0.1 and no h(125)-H mixing, H + → c b ¯ $$ c\overline{b} $$ decay is dominant, and the c ¯ b c ¯ b $$ \overline{c}b\overline{c}b $$ final state is likely overwhelmed by QCD background at the LHC. We show that the electroweak production of H + H − at the ILC is discoverable with integrated luminosity of 1 ab −1. Furthermore, we show that m H + $$ {m}_{H^{+}} $$ can be extracted by requiring the two pairs of b and light jets be roughly equal in mass, without assuming the mass value. Thus, ILC can probe low mass Higgs bosons in multijet final states to complement HL-LHC in the future.

Keywords

• Beyond Standard Model
• e +-e − Experiments
• FCNC Interaction
• Flavour Changing Neutral Currents
• Higgs Physics