Comparison between μ^-μ^+ and e^-e^+ colliders for charged Higgs production in 2HDM

We study the phenomenology of the charged Higgs boson at future muon colliders. We investigate both the pair production μ^+ μ^- → H^+ H^-, the single production μ^+ μ^- → W^± H^∓, as well as the Vector Boson Fusion (VBF) {e^+e^-, μ^+ μ^-}→νν̅ H^+ H^-. We show that the neutral Higgs exchange diagrams in the muon collider case can lead to a significant boost in the cross sections through their Yukawa couplings. Our results for the muon collider are systematically compared to the corresponding ones at e^+e^- machines. It is demonstrated that the vector boson fusion (VBF) e^+e^- →νν̅ H^+ H^- can compete with the mentioned 2→ 2 processes. We select benchmark points and perform signal-background analyses, taking into account detector simulations. We demonstrate the discovery region at 5σ and the excluded region at 2σ levels at a 3 TeV muon collider.