Search

We study a class of models for neutrino mass matrix in Type-II seesaw with A 4 family symmetry. The resulting neutrino mass matrix can be naturally made to respect a μ – τ exchange plus CP conjugate symmetry (GLS) with the CP violating phase δ and the mixing angle θ 23 predicted to be ± π / 2 and π / 4 , respectively. When GLS is explicitly broken by complex Yukawa couplings, the model predictions for δ and θ 23 can be significantly modified. Should future experiments indeed determine θ 23 and δ CP away from the GLS limit values, one then had to consider models with broken GLS. We study several simple scenarios to show how the modifications arise w̱hen GLS is broken and how future experiments can test this class of models. [ABSTRACT FROM AUTHOR]

Several baryons containing a heavy b-quark have been discovered. The decays of these states provide new platform for testing the standard model (SM). We study CP violation in SM for charmless two-body decays of the flavor SU ( 3 ) anti-triplet beauty baryon (b-baryon) B = ( Ξ b − , Ξ b 0 , Λ b 0 ) in a model independent way. We found, in the flavor SU ( 3 ) symmetry limit, a set of new predictive relations among the branching ratio Br and CP asymmetry A CP for B decays, such as A CP ( Ξ b − → K 0 Ξ − ) / A CP ( Ξ b − → K ¯ 0 Σ − ) = − Br ( Ξ b − → K ¯ 0 Σ − ) / Br ( Ξ b − → K 0 Σ − ) , A CP ( Λ b 0 → π − p ) / A CP ( Ξ b 0 → K − Σ + ) = − Br ( Ξ b 0 → K − Σ + ) τ Λ b 0 / Br ( Λ b 0 → π − p ) τ Ξ b 0 , and A CP ( Λ b 0 → K − p ) / A CP ( Ξ b 0 → π − Σ + ) = − Br ( Ξ b 0 → π − Σ + ) τ Λ b 0 / Br ( Λ b 0 → K − p ) τ Ξ b 0 . Future data from LHCb can test these relations and also other relations found. [ABSTRACT FROM AUTHOR]

Abstract: We carry out a U-spin symmetry analysis for CP violation in decays into three light , , and mesons. We clarify some subtle points in constructing decay amplitudes with formed by the two negatively charged light mesons in the final states. U-spin conserving momentum independent and momentum dependent decay amplitudes, and U-spin violating decay amplitudes due to quark mass difference are constructed. [Copyright &y& Elsevier]

Abstract: We study the complementarity between quark and lepton mixing angles (QLC), the sum of an angle in quark mixing and the corresponding angle in lepton mixing is . Experimentally in the standard PDG parametrization, two such relations exist approximately. These QLC relations are accidental which only manifest themselves in the PDG parametrization. We propose reparametrization invariant expressions for the complementarity relations in terms of the magnitude of the elements in the quark and lepton mixing matrices. In the exact QLC limit, it is found that and . Expressions with deviations from exact complementarity are obtained. Implications of these relations are also discussed. [Copyright &y& Elsevier]

Abstract: The CKM matrix describing quark mixing with three generations can be parameterized by three Euler mixing angles and one CP violating phase. In most of the parameterizations, the CP violating phase chosen is not a directly measurable quantity and is parameterization dependent. In this work, we propose to use the most accurately measured CP violating angle β in the unitarity triangle as the phase in the CKM matrix, and construct an explicit β parameterization. We also derive an approximate Wolfenstein-like expression for this parameterization. [Copyright &y& Elsevier]