We present a search for the charged Higgs boson via $e^+ e^-→H^+ H^-→b ̅cbc ̅$ at the 500 GeV ILC. In a general two Higgs doublet model without $Z_{2}$ symmetry, extra Yukawa couplings such as $\rho_{tc}$ and $\rho_{tt}$ can drive baryogenesis, but searches at the HL-LHC may still come away empty-handed. In this report, we take $m_(H^+ )=m_H=m_A=200$ GeV with $\rho_{tc}=\rho_{tt}=0.1$, and no...
We explore a novel possibility that dark matter has a light mass below 1 GeV in a lepton portal dark matter model. There are Yukawa couplings involving dark matter, left-handed leptons and an extra scalar doublet in the model. In the light mass region, dark matter is thermally produced via its annihilation into neutrinos. In order to obtain the correct relic abundance, a neutral scalar is...
The scenario of electroweak baryogenesis in the CP violating extended Higgs model has been strongly limited by current EDM experiments, hence it is difficult to generate the observed baryon density in our universe. Recently, in the CP violating Two Higgs doublet model, which has the SM like coupling of the 125GeV Higgs and the yukawa sector avoiding FCNC, it was shown that the EDM constraints...
We investigate the structure of the Higgs potential in gauge-Higgs unification with a flat extra dimension. As a viable gauge-Higgs unification model, we take the one where the Standard Model Higgs doublet is embedded into a higher-dimensional SU(3)w gauge multiplet and relax five-dimensional Lorentz symmetry. In this model, the deviation in the triple Higgs boson coupling from its SM...
We study the Higgs boson decays h -> c cbar, b bbar, b sbar, photon photon and gluon gluon in the Minimal Supersymmetric Standard Model (MSSM) with general quark flavor violation (QFV), identifying the h with the Higgs boson with a mass of 125 GeV. We compute the widths of the h decays to c cbar, b bbar, b sbar (s bbar) at full one-loop level in the MSSM with QFV. For the h decays to photon...
Many new physics scenarios beyond the Standard Model (BSM) often necessitate the existence of new neutral and/or charged scalar fields, which might couple to the SM charged leptons and thus give some BSM signals while evading all existing constraints. We show that future lepton colliders provide a clean environment to probe these BSM including some interesting lepton flavor violating (LFV)...
