Pair production of Higgs boson in NMSSM at the LHC with next-to-lightest CP-even Higgs boson being SM-like

Abstract

The next-to-minimal supersymmetric standard model (NMSSM) more naturally accommodates a Higgs boson with a mass of approximately 125 GeV than the minimal supersymmetric standard model (MSSM). In this work, we assume that the next-to-lightest CP-even Higgs boson $h_2$ is the SM-like Higgs boson $h$, whereas the lightest CP-even Higgs boson $h_1$ is dominantly singlet-like. We discuss the $h_1{h}_1$, $h_2{h}_2$, and $h_1{h}_2$ pair production processes via gluon-gluon fusion at the LHC for an collision energy of 14 TeV, and we consider the cases in which one Higgs boson decays to $b\bar{b}$ and the other one decays to $\gamma \gamma$ or ${\tau }^{+}{\tau }^{-}$. We find that, for $m_{h_1}\lesssim$ 62 GeV, the cross section of the $gg\to h_1{h}_1$ process is relatively large and maximally reaches 5400 fb, and the production rate of the $h_1{h}_1\to b\bar{b}{\tau }^{+}{\tau }^{-}$ final state can reach 1500 fb, which make the detection of this final state possible for future searches of an integrated luminosity of 300 and 3000 $f{b}^{-1}$. This is mainly due to the contributions from the resonant production process $pp\to h_2\to h_1{h}_1$ and the relatively large branching ratio of $h_1\to b\bar{b}$ and $h_1\to {\tau }^{+}{\tau }^{-}$. The cross sections of the $pp\to h_2{h}_2$ and $pp\to h_1{h}_2$ production processes maximally reach 28 fb and 133 fb, respectively.

Comments: 13 pages, 5 figures, It is to be published in Chinese Physics C