Heavy charged Higgs boson production at next generation $e^{\pm }\gamma$ colliders

Abstract

We assess the potential of future electron-positron linear colliders operating in the $e^{\pm }\gamma$ mode in detecting charged Higgs bosons with mass around and larger than the top quark mass, using Compton back-scattered photons from laser light. We compare the pair production mode, $e^{-}\gamma \to e^{-}{H}^{+}{H}^{-}$, to a variety of channels involving only one charged Higgs scalar in the final state, such as the tree-level processes $e^{-}\gamma \to {\nu }_e{H}^{-}{\Phi }^0$ (${\Phi }^0=h^0,H^0$ and $A^0$) and $e^{-}\gamma \to {\nu }_{e}f\bar{f}{H}^{-}$ ($f=b,\tau$ and ${\nu }_{\tau }$) as well as the loop-induced channel $e^{-}\gamma \to {\nu }_e{H}^{-}$. We show that, when the charged Higgs boson mass is smaller than or comparable to half the collider energy, ${\sqrt{s}}_{ee}\text{gsim}2M_{H^{\pm }}$, single production cross sections are of the same size as the pair production rate, whereas, for charged Higgs boson masses larger than ${\sqrt{s}}_{ee}/2$, all processes are heavily suppressed. In general, production cross sections of charged Higgs bosons via $e^{\pm }\gamma$ scatterings are smaller than those induced at an $e^{+}{e}^{-}$ collider and the latter represents a better option to produce and analyse such particles.

Comments: 18 pages, latex, 9 figures