arXiv subjects

A. M. Teixeira

Publications and source records attributed to A. M. Teixeira.

57 records · Page 4Linked to original sources

arXiv2002

Flavor-dependent CP violation and electroweak baryogenesis in supersymmetric theories

We analyze electroweak baryogenesis in supersymmetric theories with flavor-dependent CP-violating phases. We generalize the standard approach to include the flavor dependence of the CP-violating sources and obtain an analytical approximate expression for the baryon asymmetry of the universe induced by these sources. It is shown that in the framework where the $μ$-term is real and the chargino sources vanish, large flavor mixing might lead to a substantial baryon asymmetry through the squark contributions, once the condition to have a strong first-order phase transition induced by light right-handed up squarks is relaxed. We derive model independent bounds on the relevant up-squark left-right mass insertions. We show that in supersymmetric models with non-minimal flavor structure these bounds can be reached and the required baryon asymmetry can be generated, while satisfying the constraints coming from the electric dipole moments.

hep-ph↗

arXiv2001

Spontaneous CP Violation in the Next-to-Minimal Supersymmetric Standard Model

We re-examine spontaneous $\cp$ violation (SCPV) at the tree level in the context of the next-to-minimal supersymmetric standard model (NMSSM) with two Higgs doublets and a gauge singlet field. We analyse the most general Higgs potential without a discrete $Z_3$ symmetry, and derive an upper bound on the mass of the lightest neutral Higgs boson. We estimate $\epsi_K$ by applying the mass insertion approximation, finding that in order to account for the for the observed $\cp$ violation in the neutral kaon sector a non-trivial flavour structure in the soft-breaking $A$ terms is required and that the upper bound on the lightest Higgs-boson mass becomes stronger. We also discuss the implications of electric dipole moments of the electron and the neutron in SUSY models with SCPV.

hep-ph↗

arXiv2001

Spontaneous CP Violation in the Next-to-Minimal Supersymmetric Standard Model Revisited

We re-examine spontaneous CP violation at the tree level in the context of the next-to-minimal supersymmetric standard model (NMSSM) with two Higgs doublets and a gauge singlet field. We analyse the most general Higgs potential without a discrete Z_3 symmetry, and derive an upper bound on the mass of the lightest neutral Higgs boson consistent with present experimental data. We investigate, in particular, its dependence on the admixture and CP-violating phase of the gauge singlet field, as well as on tan(beta). To assess the viability of the spontaneous CP violation scenario, we estimate epsilon_K by applying the mass insertion approximation. We find that a non-trivial flavour structure in the soft-breaking A terms is required to account for the observed CP violation in the neutral kaon sector. Furthermore, combining the minimisation conditions for spontaneous CP violation with the constraints coming from K0-K0bar mixing, we find that the upper bound on the lightest Higgs-boson mass becomes stronger. We also point out that the electric dipole moments of electron and neutron are a serious challenge for SUSY models with spontaneous CP violation.

hep-ph↗