Observability of Charged Higgs Contribution in t-channel Single Top at LHC

Abstract

In this paper, the charged Higgs contribution in t-channel single top production is studied. The production process is a t-channel single top event with charged Higgs exchange. Therefore the signal is similar with Standard Model single top production in terms of the final state. In the first step, the signal cross section is calculated and compared to the other main production processes which are used for a heavy charged Higgs search at LHC, i.e., $pp\rightarrow t\bar {b}H^{-}$ and $pp\rightarrow H^{+} \rightarrow t\bar {b}$. In the next step, an event generation and analysis is applied on signal and background events, in order to estimate the signal significance. The signal cross section is typically smaller than the associated production ($t\bar {b}H^{-}$) and resonance production ($t\bar {b}$) by a factor of 10⁻³ and ranges from 10 f b to 1 f b for charged Higgs mass from 200 to 500 GeV at tanβ = 50. Due to the small cross section of signal events and large SM background, the signal significance is small even after a dedicated kinematic analysis and selection of events, however, tanβ values above 120 can be excluded at an integrated luminosity of 3000 f b ⁻¹.