Double and Triple Higgs Boson Production at Future Linear Colliders

Abstract: In this paper such processes which act as a source of double Higgs production (2H) as well as triple Higgs production (3H) at future linear colliders are analyzed with in 2HDM and its special type-II, MSSM at various center of mass energies. The main aim of this study is to compute and also compare the cross-sections in double and triple Higgs production processes at the future linear colliders. The production of double charged Higgs boson ($H<sup>{+}H<sup>{-}$) as well as triple Higgs boson ($H<sup>{+}H<sup>{-}H<sup>{0}$),($H<sup>{+}H<sup>{-}h<sup>{0}$) are considered for study at two center of mass energies (1.5 TeV and 3 TeV) within two models 2HDM and MSSM at future linear colliders. It is observed that for double charged Higgs production process (H${}<sup>{+}$H${}<sup>{-}$) the resulting cross-section values are almost same in both the models (in 2HDM and MSSM). On the other hand in the case of Triple Higgs production process ($H<sup>{+}H<sup>{-}H<sup>{0}$), ($H<sup>{+}H<sup>{-}h{0}$) several orders of enhancement in cross-sections is observed in 2HDM as compared to MSSM. Similarly two types of processes, neutral Higgs pair production ($A^{0} H<sup>{0}$) as well as ($A^{0} h<sup>{0}$) and triple neutral Higgs production ($h^{{0}h^{{0}A^{{0}$) is analyzed in 2HDM type-I at the future linear ${\mu}^{{+}${\mu}^{-\ }$$collider for various values of center of mass energies from 500 GeV to 3000 GeV (0.5 TeV to 3 TeV). It is observed that the cross-section for neutral Higgs pair production ($$A^{0} h^{0})}processiscomparativelygreaterthanthatofneutralHiggspairproduction()} process is comparatively greater than that of neutral Higgs pair production (A^{0} H^{0})}process.SimilarlyforneutralHiggsTripleproduction()} process. Similarly for neutral Higgs Triple production (h^{0}h^{0}A^{0}$) an enhancement is seen in cross-sections with increase of tan{\ss}.