4,382 research outputs found
Sizable CP Violation in the Bosonized Standard Model
Using the worldline method, we derive an effective action of the bosonic
sector of the Standard Model by integrating out the fermionic degrees of
freedom. The CP violation stemming from the complex phase in the CKM matrix
gives rise to CP-violating operators in the one-loop effective action in the
next-to-leading order of a gradient expansion. We calculate the prefactor of
the appropriate operators and give general estimates of CP violation in the
bosonic sector of the Standard Model. In particular, we show that the effective
CP violation for weak gauge fields is not suppressed by the Yukawa couplings of
the light quarks and is much larger than the bound given by the Jarlskog
determinant.Comment: 15 pages, minor changes, published versio
Unifying CP violations of quark and lepton sectors
A preliminary determination of the Dirac phase in the PMNS matrix is
\dell\approx -\frac{\pi}{2}. A rather accurately determined Jarlskog
invariant in the CKM matrix is close to the maximum. Since the phases in
the CKM and PMNS matrices will be accurately determined in the future, it is an
interesting problem to relate these two phases. This can be achieved in a
families-unified grand unification if the weak CP violation is introduced
spontaneously {\it \`a la} Froggatt and Nielsen at a high energy scale, where
only one meaningful Dirac CP phase appears.Comment: 10 pages with 3 figure
Plans for Kaon Physics at BNL
I give an overview of current plans for kaon physics at BNL. The program is
centered on the rare decay modes K+ --> pi+ nu nubar and KL --> pi0 nu nubar.Comment: 10 pages, 8 figures. Uses espcrc2.sty. For the proceedings of HIF04:
High Intensity Frontier Workshop, La Biodola, Isola D'Elba, June 5-8, 200
Quark-lepton mass unification at TeV scales
A scenario combining a model of early (TeV) unification of quarks and leptons
with the physics of large extra dimensions provides a natural mechanism linking
quark and lepton masses at TeV scale. This has been dubbed as early
quark-lepton mass unification by one of us (PQH) in one of the two models of
early quark-lepton unification, which are consistent with data, namely SU(4)_PS
\otimes SU(2)_L \otimes SU(2)_R \otimes SU(2)_H. In particular, it focused on
the issue of naturally light Dirac neutrino. The present paper will focus on
similar issues in the other model, namely SU(4)_PS \otimes SU(3)_L \otimes
SU(3)_H.Comment: Accepted for publication in PRD: The new version is in agreement with
the accepted manuscrip
Triangular Textures for Quark Mass Matrices
The hierarchical quark masses and small mixing angles are shown to lead to a
simple triangular form for the U- and D-type quark mass matrices. In the basis
where one of the matrices is diagonal, each matrix element of the other is, to
a good approximation, the product of a quark mass and a CKM matrix element. The
physical content of a general mass matrix can be easily deciphered in its
triangular form. This parameterization could serve as a useful starting point
for model building. Examples of mass textures are analyzed using this method.Comment: 10 pages, no figure
Determining fundamental parameters from the chargino sector in Left-Right Supersymmetric models
Analytical expressions relating the fundamental parameters describing the
chargino sector in the context of the Left-Right Supersymmetric model are
constructed. A general complex extension of the real non-symmetric chargino
mass matrix including all possible CP-violating phases is considered. The
method used for such a effects is the projector formalism based on the explicit
knowledge of two unitary matrices diagonalizing the chargino mass matrix. Some
possible scenarios allowing us to extract analytical and numerical values for
the unknown parameters are considered. Moreover, an algorithm allowing us to
disentangle the fundamental parameters of the chargino sector, based on
possible measurements of some class of cross-section observables related to the
chargino pair production in annihilation processes, is described.
Some comparisons with the corresponding results in the context of the Minimal
Supersymmetric Standard Model are given.Comment: 48 pages, 13 figure
A description of the neutralino observables in terms of projectors
Applying Jarlskog's treatment of the CKM matrix, to the neutralino mass
matrix in MSSM for real soft gaugino SUSY breaking and -parameters, we
construct explicit analytical expressions for the four projectors which acting
on any neutralino state project out the mass eigenstates. Analytical
expressions for the neutralino mass eigenvalues in terms of the various SUSY
parameters, are also given. It is shown that these projectors and mass
eigenvalues are sufficient to describe any physical observable involving
neutralinos, to any order of perturbation theory. As an example, the cross section at tree level is given in
terms of these projectors. The expected magnitude of their various matrix
elements in plausible SUSY scenarios is also discussed.Comment: 14 pages, no figures. Version to appear in Phys. Rev. D. e-mail:
[email protected]
A Predictive Minimal Model for Neutrino Masses and Mixings
A model is considered in which the scale of the heavy singlet neutrinos is a
few orders of magnitude below the grand unification scale and where
right-handed vector bosons play still a negligible role. In a basis with
diagonal up-quark and Dirac-neutrino mass matrices it is assumed that the heavy
neutrino mass matrix has only zero elements in its diagonal, in analogy to the
light neutrino mass matrix in the Zee model. Connecting then the remaining
matrix elements with the small parameter describing the hierarchy of quark
masses and mixings and by assuming commutativity of the charged lepton with the
down-quark mass matrix, the calculation of all neutrino properties can be
performed in terms of the two mass differences relevant for atmospheric and
solar neutrino oscillations. CP-violation is directly related to CP-violation
in the quark sector.Comment: revtex, 9 pages, two references added, to be published in Phys. Rev.
D presented at Neutrino' 2000, Sudbury, Canad
CP Violation for Leptons at Higher Energy Scales
The phase convention independent measure of CP violation for three
generations of leptons is evaluated at different energy scales. Unlike in the
quark sector, this quantity does not vary much between the weak and the grand
unification scales. The behavior of the measure of CP violation in the Standard
Model is found to be different from that in the extensions of the Standard
Model.Comment: 10 pages, 2 figures, references added, typos correcte
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