Constraints on doubly charged Higgs interactions at linear collider

Abstract Production of a single doubly charged Higgs boson Δ −− in polarized e + e − and e + γ collision modes of the linear collider have been investigated. The mass range of Δ −− to be probed extends up to the collision energy. The diagonal lepton number violating Yukawa coupling h ee will be tested at least three orders of magnitude more strictly than in present experiments.