SPONTANEOUS CP-VIOLATION WITHIN THE FRAMEWORK OF SU(2)L×SU(2)R×U(1) MODELS WITH MANIFEST CP INVARIANCE REVISITED

1992 ◽  
Vol 07 (25) ◽  
pp. 6325-6337
Author(s):  
P. BASAK ◽  
A. DATTA

The case of spontaneous CP violation for large mt is reanalyzed and the validity of perturbation theory is checked by calculating the second order corrections to the CKM matrix. For a very large right-handed mass scale, the perturbation theory breaks down in some cases. While in other cases consistent with perturbation theory, the model predicts too large ε′/ε. Two possible alternatives are: (a) models with low right-handed mass scales with three generations and (b) models with heavy right-handed mass scales with four generations, avoid the above problems and values of ε′/ε and electric dipole moment of the neutron consistent with present data are obtained.

2006 ◽  
Vol 21 (03) ◽  
pp. 243-264 ◽  
Author(s):  
MÜGE BOZ

We study the explicit CP violation of the Higgs sector in the next-to-minimal supersymmetric model with a gauge singlet Higgs field. Our numerical predictions show that electric dipole moment of electron lies around the present experimental upper limits. The mass of the lightest Higgs boson is quite sensitive to the CP violating phases in the theory. It is observed that as the vacuum expectation value of the singlet gets higher values, CP violation increases.


2018 ◽  
Vol 175 ◽  
pp. 01014 ◽  
Author(s):  
Boram Yoon ◽  
Tanmoy Bhattacharya ◽  
Rajan Gupta

For the neutron to have an electric dipole moment (EDM), the theory of nature must have T, or equivalently CP, violation. Neutron EDM is a very good probe of novel CP violation in beyond the standard model physics. To leverage the connection between measured neutron EDM and novel mechanism of CP violation, one requires the calculation of matrix elements for CP violating operators, for which lattice QCD provides a first principle method. In this paper, we review the status of recent lattice QCD calculations of the contributions of the QCD Θ-term, the quark EDM term, and the quark chromo-EDM term to the neutron EDM.


1969 ◽  
Vol 47 (6) ◽  
pp. 693-695 ◽  
Author(s):  
Radha Gourishankar ◽  
A. N. Kamal

A model of CP violation due to the existence of a neutral intermediate weak vector boson is studied. It is found that all leptonic and semileptonic decays are CP conserving; however nonleptonic decays are all CP violating to order [Formula: see text]. The CP-violating decays also preserve the [Formula: see text]. An estimate of the electric dipole moment of the nucleon based on such a model gives μe ≈ 10−29 e cm. The electric dipole moment of the electron is zero.


2007 ◽  
Vol 85 (6) ◽  
pp. 597-606
Author(s):  
A Ritz

We dicuss the utility of precision probes for flavour-diagonal CP-violation, namely, searches for electric dipole moments of nucleons, atoms, and molecules, in looking for new physics thresholds that manifest themselves primarily through higher dimensional operators. After reviewing the status of the electric dipole moment (EDM) constraints, we consider first the sensitivity to a generic class of dimension-five operators generated at a supersymmetric threshold, through their contribution to CP- and flavour-violating observables. Such thresholds can be probed by EDMs up to a scale of order 108 GeV depending on the flavour structure. We then turn to consider the possibility that electroweak baryogenesis is made feasible by the introduction of dimension-six operators at a TeV-scale threshold. The EDM costraints on dimension-six couplings of the Higgs to the fermions currently still allow a reasonable window in parameter space for these models, but the next generation of experiments should provide a conclusive test. PACS Nos.: 11.30.Er, 12.60.Fr, 12.60.Jv


2002 ◽  
Vol 17 (23) ◽  
pp. 1489-1497 ◽  
Author(s):  
C. Q. GENG ◽  
J. N. NG ◽  
T. H. WU

We study the CP violating effects in the decay of η → π+π- γ. We show that to have CP violation in the decay, one has to consider both linear and circular photon polarizations. In the standard model, the polarizations are vanishingly small. However, model independently, i.e. using only experimental constraint imposed by the limit on Br (η → π+ π-), it can be up to O(10%). We also explore various possible operators and we find that the tensor type operator, possibly arising from a nonzero CP violating electric dipole moment of the strange quark, can induce a sizable linear photon polarization.


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