Charm associated production of the pseudoscalar Higgs boson $h^{\prime \prime }$ in the MCPM' at the LHC

Abstract

We discuss charm associated production of the pseudoscalar Higgs boson $h^{\prime \prime }$ in the MCPM'. In our analysis we assume $m_{h^{\prime \prime }}$ = 95.4 GeV, which corresponds to an enhancement observed by the CMS collaboration in the $\gamma \gamma$ channel. As discussed recently, the MCPM' is consistent with the CMS enhancement. In this model the $h^{\prime \prime }$ Higgs boson of this mass decays dominantly into $c\bar{c}$ jets. The cross section for the associated $h^{\prime \prime }$ production in $pp\to h^{\prime \prime }c\bar{c}$ is found to be almost as big as that for the Drell-Yan (DY) $c\bar{c}\to h^{\prime \prime }$ production, much larger than that for two-gluon fusion $gg\to h^{\prime \prime }$. Since in the MCPM' the dominant $h^{\prime \prime }$ decay is into the $c\bar{c}$ channel we have to deal with the $pp\to c\bar{c}c\bar{c}$ process with $c$ and $\bar{c}$ jets. In addition to the signal processes, we have sizeable single parton scattering (SPS) and double parton scattering (DPS) nonresonant background. In our analysis we include diagrams of gluon-gluon fusion $gg\to h^{\prime \prime }$ which lead to the $c\bar{c}c\bar{c}$ final state. We discuss also the possible role of the reaction $pp\to h^{\prime \prime }{h}^{\prime \prime }$. Assuming 100\% c and $\bar{c}$ jet tagging we discuss in detail how to improve the signal-to-background ratio. Our analysis shows promising resonance-like enhancements and relatively large cross sections in the $c\bar{c}c\bar{c}$ channel within the MCPM'. In an appendix we discuss the total cross section for $h^{\prime \prime }$ production at the LHC. We also compare distributions for the reactions $pp\to h^{\prime \prime }X$ and $pp\to ZX$ with $h^{\prime \prime }$ and $Z$ decaying to $c\bar{c}$ and ${\mu }^{+}{\mu }^{-}$. We hope that the LHC collaborations will in the future perform the experimental studies corresponding to the theoretical studies discussed here.

Comments: 29 pages, 26 figures