38 research outputs found
Flavor changing neutrino interactions and CP violation in neutrino oscillations
We investigate the interference effects of non-standard neutrino-matter
interactions (NSNI) with the mass-induced neutrino oscillations. The NSNI is
composed of flavor-changing neutrino interactions (FCNI) and flavor-diagonal
neutrino interactions (FDNI). Both of the interactions are introduced in the
\nu_\mu -\nu_\tau sector and the \nu_e -\nu_\mu sector in order to study their
effects in \nu_\mu\to\nu_\tau and \nu_\mu\to\nu_e oscillations, respectively.
The FCNI effect proves to possibly dominate the CP violating effect and
significantly survive as a fake CP violating effct in the neutrino energy
region where the pure CP violating effect, ordinary matter effect and FDNI
effect fall, for example, above 4 GeV at the baseline of L=730 km in the
\nu_\mu\to\nu_\tau oscillation for the maximum parameter values of FCNI and
FDNI allowed by the atmospheric neutrino oscillation data. The FCNI and FDNI
effects on CP violation in the oscillation are negligibly
small due to the stringent constraints on FCNI from the bounds on lepton flavor
violating processes and on FDNI from the limits on lepton universality
violation.Comment: 18 pages in LaTeX2e, 12 ps figures. The discussion of detectability
of the CP violation is delete
Are the New Physics Contributions from the Left-Right Symmetric Model Important for the Indirect CP Violation in the Neutral B Mesons?
Several works analyzing the new physics contributions from the Left-Right
Symmetric Model to the CP violation phenomena in the neutral B mesons can be
found in the literature. These works exhibit interesting and experimentally
sensible deviations from the Standard Model predictions but at the expense of
considering a low right scale \upsilon_R around 1 TeV. However, when we stick
to the more conservative estimates for \upsilon_R which say that it must be at
least 10^7 GeV, no experimentally sensible deviations from the Standard Model
appear for indirect CP violation. This estimate for \upsilon_R arises when the
generation of neutrino masses is considered. In spite of the fact that this
scenario is much less interesting and says nothing new about both the CP
violation phenomenon and the structure of the Left-Right Symmetric Model, this
possibility must be taken into account for the sake of completeness and when
considering the see-saw mechanism that provides masses to the neutrino sector.Comment: LaTex file. 19 pages, 4 figures. Change in the way the paper address
the problem. As a result, change in title, abstract, and some sections.
Conclusions unchanged. Version to appear in Foundations of Physics Letter
On Testing V-A in Lambda_b Decays
We comment on a recent suggestion by Amundson, Rosner, Worah and Wise to test
the chirality of the -quark decay coupling via polarized baryons
produced in . We study the effect
of contributions from an amplitude in which a right-handed to current
couples to a V-A lepton current.Comment: (6 pages, PHYZZX, 1 figure, available upon request), SLAC-PUB-589
Effects of the and of other processes on the mixing hierarchies in the four-generation model
We analyze in the four-generation model the first measurement of the
branching ratio of rare kaon decay , along with the
other processes of mass difference , CP-violating
parameter mixing, mixing,
, and the upper bound values of mixing
and , and try to search for mixing of the fourth
generation in the hierarchical mixing scheme of the Wolfenstein
parametrization. Using the results for the mixing of the fourth generation, we
discuss predictions of the mixing () and the
branching ratio of directly CP-violating decay process
, and the effects on the CP asymmetry in neutral B
meson decays and the unitarity triangle.Comment: 29 pages written in LaTex. 6 figures(drawn on LaTeX). Revised from
" in the four-generation model" of the same
Authors(TOKUSHIMA 99-1, January 1999). A minor chang
CP violation effect in long-baseline neutrino oscillation in the four-neutrino model
We investigate CP-violation effect in the long-baseline neutrino oscillation
in the four-neutrino model with mass scheme of the two nearly degenerate pairs
separated with the order of 1 eV, by using the data from the solar neutrino
deficit, the atmospheric neutrino anomaly and the LSND experiments along with
the other accelerator and reactor experiments. By use of the most general
parametrization of the mixing matrix with six angles and six phases, we show
that the genuine CP-violation effect could attain as large as 0.3 for and that the matter effect is negligibly
small such as at most 0.01 for for , which is the mass-squared difference relevant
to the long-baseline oscillation.Comment: 21 pages in LaTeX, 9 ps figures. Some changes in the Introduction and
Reference
New Physics in CP Asymmetries and Rare B Decays
We review and update the effects of physics beyond the standard model on CP
asymmetries in B decays. These asymmetries can be significantly altered if
there are important new-physics contributions to \bqbqbar mixing. This same new
physics will therefore also contribute to rare, flavor-changing B decays.
Through a study of such decays, we show that it is possible to partially
distinguish the different models of new physics.Comment: 42 pages, plain TeX (macros included), 1 figure (included). A few
sentences added, references updated. Present manuscript is now identical to
the version accepted for publication in Phys. Rev.