Search

Two opposite charged new heavy gauge boson pair production at the Large Hadron Collider (LHC) is presented in this paper. These bosons are known as $W^{'}$ boson due to the reason that it is the heavy version of Standard Model's weak force carrier, the $W$ boson. The production cross section and decay width in proton-proton ($pp$) collision at \sqrts~= 8 TeV are calculated for different masses and coupling strengths of $W^{'}$. Efficiencies for different signal regions and branching ratios for different decay channels are computed. In this study, the pair production ($W^{'^{+}}W^{'^{-}}$) is considered in emerging new physics as a result of $pp$ collision at \sqrts~= 8 TeV at the LHC with final state containing two tau ($\tau$) leptons and two neutrinos (each $W^{'}$ decay to $\tau$ and its neutrino). The event selection efficiency similar to the CMS experiment is used for the mass of $W^{'}$ to set lower limits for different coupling strengths of $W^{'}$ and results are presented in this work. For heavy gauge bosons, when coupling strength is similar to that of Standard Model's $W$ boson, the mass of $W^{'}$ below 305 GeV are excluded at confidence level of $95\%$., Comment: 21 pages, 16 figures

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 ($H^{+}H^{-}$) as well as triple Higgs boson ($H^{+}H^{-}H^{0}$),($H^{+}H^{-}h^{0}$) 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${}^{+}$H${}^{-}$) 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 ($H^{+}H^{-}H^{0}$), ($H^{+}H^{-}h{0}$) several orders of enhancement in cross-sections is observed in 2HDM as compared to MSSM. Similarly two types of processes, neutral Higgs pair production ($A^{0} H^{0}$) as well as ($A^{0} h^{0}$) 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 ($A^{0} h^{0}$) process is comparatively greater than that of neutral Higgs pair production ($A^{0} H^{0}$) 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}., Comment: 14 pages