Comparison between μ−μ+ and e−e+ colliders for charged Higgs production in the 2HDM

We study the phenomenology of the charged Higgs boson at future muon colliders. We investigate 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−→νν¯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 VBF e+e−→νν¯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. Published by the American Physical Society 2024