Higgs Bosons in the Two-Doublet Model with CP Violation

We consider the effective two-Higgs-doublet potential with complex parameters, when the CP invariance is broken both explicitly and spontaneously. Diagonal mass term in the local minimum of the potential is constructed for the physical basis of Higgs fields, keeping explicitly the limiting case of CP-conservation if the parameters are taken real. For special case of the two-doublet Higgs sector of the minimal supersymmetric model, when CP invariance is violated by the Higgs bosons interaction with scalar quarks of the third generation, we calculate by means of the effective pothential method the Higgs boson masses and evaluate the two-fermion Higgs boson decay widths and the widths of rare one-loop mediated decays H -> \gamma \gamma, H -> gg.Comment: 36 pages, 5 tables, 9 figures. References added, minor changes in the text, misprint in the g_{hH^+H^-}, page 22, corrected, 'direct' diagonalization procedure described in section 3.

Triple and quartic interactions of Higgs bosons in the two-Higgs-doublet model with CP violation

We consider the two-Higgs-doublet model with explicit CP-violation, where the effective Higgs potential is not CP-invariant at the tree-level. Three neutral Higgs bosons of the model are the mixtures of CP-even and CP-odd bosons which exist in the CP-conserving limit of the theory. The mass spectrum and tree-level couplings of the neutral Higgs bosons to gauge bosons and fermions are significantly dependent on the parameters of the Higgs boson mixing matrix. We calculate the Higgs-gauge boson, Higgs-fermion, triple and quartic Higgs self-interactions in the MSSM with explicit CP-violation in the Higgs sector and CP-violating Yukawa interactions of the third generation scalar quarks. In some regions of the MSSM parameter space substantial changes of the self-interaction vertices take place, leading to significant suppression or enhancement of the multiple Higgs boson production cross sections.Comment: 29 pages, 4 figures. Minor changes in section 3, misprints in (47) corrected. Version accepted by EPJ

Mott-Anderson freeze-out and the strange matter "horn"

We discuss the $\sqrt{s}$-dependence of the $K^+/\pi^+$ ratio in heavy-ion collisions (the "horn" effect) within a Mott-Anderson localization model for chemical freeze-out. The different response of pion and kaon radii to the hot and dense hadronic medium results in different freeze-out conditions. We demonstrate within a simple model that this circumstance enhances the "horn" effect relative to statistical models with universal chemical freeze-out.Comment: 8 pages, 4 figure