Alternative theories of CP violation (original) (raw)

Rare Decays and CP Violation Beyond the Standard Model

International Journal of Modern Physics A, 2006

We review the status of rare decays and CP violation in extensions of the Standard Model. We analyze the determination of the unitarity triangle and the model-independent constraints on new physics that can be derived from this analysis. We find stringent bounds on new contributions to [Formula: see text] and [Formula: see text] mixing, pointing either to models of minimal flavour violation or to models with new sources of flavour and CP violation in b → s transitions. We discuss the status of the universal unitarity triangle in minimal flavour violation, and study rare decays in this class of models. We then turn to supersymmetric models with nontrivial mixing between second and third generation squarks, discuss the present constraints on this mixing and analyze the possible effects on CP violation in b → s nonleptonic decays and on [Formula: see text] mixing. We conclude presenting an outlook on Lepton-Photon 2009.

Complex flavour couplings in supersymmetry and unexpected CP violation in the decay B→ φK

Physics Letters B, 2001

Complex flavour couplings (off-diagonal mass terms) in the squark sector of supersymmetric theories may drastically alter both the rate and the CP -violating asymmetry of certain B-meson decays. We consider the effects of couplings that induce b → s transitions and lead to final state with strangeness one. We investigate the bounds that must be satisfied by the new terms and explore the possible implications on direct and mixing induced asymmetries in the charged and neutral B → J/ΨK and B → φK decays. *

CP violation beyond the standard model

Arxiv preprint hep-ph/9701231, 1997

We review CP violation in various extensions of the electroweak sector of the Standard Model. A particular emphasis is put on supersymmetric models. We describe the two CP problems of supersymmetry, concerning d N and ε K . We critically review the various mechanisms that have been suggested to solve these problems: exact universality, approximate CP symmetry, alignment, approximate universality and heavy squarks. We explain how future measurements of CP violation will test these mechanisms. We describe extensions of the quark sector and their implications on CP asymmetries in neutral B decays, on the K L → πνν decay and on ∆Γ(B s ). We discuss CP violation in charged scalar exchange in models with natural flavor conservation and explain how transverse lepton polarization in meson decays can probe such models. CP violation in neutral scalar exchange arises in models of horizontal symmetries and may be manifest in heavy quark (b and t) physics. We describe the implications of Left-Right Symmetric models on d N , ε K , ε /ε and CP asymmetries in B decays. Finally, we briefly discuss the potential of future measurements of CP violation to discover New Physics.

CP violation and flavour mixing in the standard model — 1996 update

Nuclear Physics B - Proceedings Supplements, 1997

We review and update the constraints on the parameters of the quark flavour mixing matrix V CKM in the standard model and estimate the resulting CP asymmetries in B decays, taking into account recent experimental and theoretical developments. With the updated CKM matrix we present the currently-allowed range of the ratios |V td /V ts | and |V td /V ub |, as well as the standard model predictions for the B 0 s -B 0 s mixing parameter x s (or, equivalently, ∆M s ) and the quantities sin 2α, sin 2β and sin 2 γ, which characterize the CP-asymmetries in B-decays.

$ B $ Decays, Flavour Mixings and CP Violation In the Standard Model

Arxiv preprint hep-ph/9606324, 1996

∗Lectures given at the XX International Nathiagali Summer College on Physics and Contemporary Needs, Bhurban, Pakistan, June 24 - July 13, 1995; to appear in the Proceedings (Nova Science Publishers, New York), Editors: Riazuddin, KA Shoaib et al.

Flavor-dependent CP violation and electroweak baryogenesis in supersymmetric theories

Physical Review D, 2002

We analyze electroweak baryogenesis in supersymmetric theories with flavor-dependent CPviolating 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.

Supersymmetric Models and CP violation in B decays

In this talk CP violation in the supersymmetric models, and especially in B-decays is discussed. We review our analysis of the supersymmetric contributions to the mixing CP asymmetries of BtophiKSB\to \phi K_SBtophiKS and BtoetaprimeKSB\to \eta^{\prime} K_SBtoetaprimeKS processes. Both gluino and chargino exchanges are considered in a model independent way by using the mass insertion approximation method. The QCD factorization method is used, and parametrization of this method in terms of Wilson coefficients is presented in both decay modes. Correlations between the CP asymmetries of these processes and the direct CP asymmetry in btosgammab\to s \gammabtosgamma decay are shown.

CP violation and the scale of supersymmetry breaking

Physical Review D, 2001

Supersymmetric models with a high supersymmetry breaking scale give, in general, large contributions to ε K and/or to various electric dipole moments, even when contributions to CP conserving, flavor changing processes are sufficiently suppressed. Some examples are models of dilaton dominance, alignment, non-Abelian flavor symmetries, heavy first two generation sfermions, anomaly mediation and gaugino mediation. There is then strong motivation for 'approximate CP', that is a situation where all CP violating phases are small. In contrast, in supersymmetric models with a low breaking scale it is quite plausible that the CKM matrix is the only source of flavor and CP violation. Gauge mediation provides a concrete example. Approximate CP is then unacceptable. Upcoming measurements of the CP asymmetry in B → ψK S might exclude or support the idea of approximate CP and consequently probe the scale of supersymmetry breaking.

B→Kπ puzzle and new sources of CP violation in supersymmetry

Physics Letters B, 2009

The difference between the CP asymmetries of the B 0 → K + π − and B + → K + π 0 decays has been recently confirmed with an evidence larger than 5σ's. We discuss it as a possible signal of new physics associated with new (large) CP violation in the electroweak penguin contributions. We propose a supersymmetry breaking scheme where such new sources of CP violation occur in the flavor non-universal trilinear scalar couplings.