75 research outputs found
B_{s,d} -> l^+ l^- and K_L -> l^+ l^- in SUSY models with non-minimal sources of flavour mixing
We present a general analysis of B_{s,d}-> l^+ l^- and K_L -> l^+ l^- decays
in supersymmetric models with non-minimal sources of flavour mixing. In spite
of the existing constraints on off-diagonal squark mass terms, these modes
could still receive sizeable corrections, mainly because of Higgs-mediated
FCNCs arising at large tan(beta). The severe limits on scenarios with large
tan(beta) and non-negligible {tilde d}^i_{R(L)}-{d-tilde}^j_{R(L)} mixing
imposed by the present experimental bounds on these modes and Delta B=2
observables are discussed in detail. In particular, we show that scalar-current
contributions to K_L -> l^+ l^- and B-{bar B} mixing set non-trivial
constraints on the possibility that B_s -> l^+ l^- and B_d -> l^+ l^- receive
large corrections.Comment: 18 pages, 4 figures (v2: minor changes, published version
Beneficial immunostimulatory effect of short-term Chlorella supplementation: enhancement of natural Killer cell activity and early inflammatory response (Randomized, double-blinded, placebo-controlled trial)
Background - In vitro and animal studies have demonstrated that Chlorella is a potent biological response modifier on immunity. However, there were no direct evidences for the effect of Chlorella supplementation on immune/inflammation response in healthy humans. Methods - This study was designed for an 8-week randomized, double-blinded, placebo-controlled trial: 5g of Chlorella (n=23) or Placebo (n=28) as form of tablets. Mainly, cytotoxic activities of Natural killer (NK) cells and serum concentrations of interferon-¿, interleukin-1ß and interleukin-12 were measured. Results - After the 8-week, serum concentrations of interferon-¿ (
Lepton flavour violating Higgs Boson decays, tau --> mu gamma and B(s) --> mu+mu- in the constrained MSSM+NR with large tan beta
Realistic predictions are made for the rates of lepton flavour violating
Higgs boson decays, tau --> mu gamma, mu --> e gamma, Bs --> mu+mu-, Bs --> tau
mu and tau --> 3mu, via a top-down analysis of the Minimal Supersymmetric
Standard Model(MSSM) constrained by SU(5) unification with right-handed
Neutrinos and large tan beta. The third family neutrino Yukawa coupling is
chosen to be of order 1, in this way our model bares a significant resemblance
to supersymmetric SO(10). In this framework the large PMNS mixings result in
potentially large lepton flavour violation. Our analysis predicts tau --> mu
gamma and mu --> e gamma rates in the region (10^{-8}-10^{-6}) and
(10^{-15}-10^{-14}) respectively. We also show that the rates for lepton
flavour violating Higgs decays can be as large as 10^{-7}. The non-decoupling
nature of H --> tau mu is observed which leads to its decay rate becoming
comparable to that for tau --> mu gamma for large values of m_0 and M_1/2. We
also find that the present bound on Bs --> mu+mu- is an important constraint on
the rate of lepton flavour violating Higgs decays. The recently measured
Bs-Bsbar mixing parameter Delta Ms is also investigated.Comment: 27 pages, 15 postscript figures, 1 table. Small changes made to the
text and title. Updated references. Bs-Bsbar analysis also include
Lepton polarization correlations in
In this work we will study the polarizations of both leptons () in the
decay channel . In the case of the dileptonic inclusive
decay , where apart from the polarization asymmetries
of single lepton , one can also observe the polarization asymmetries of
both leptons simultaneously. If this sort of measurement is possible then we
can have, apart from decay rate, FB asymmetry and the six single lepton
polarization asymmetries (three each for and ), nine more
double polarization asymmetries. This will give us a very useful tool in more
strict testing of SM and the physics beyond. We discuss the double polarization
asymmetries of leptons in the decay mode within
the SM and the Minimal Supersymmetric extensions of it.Comment: 21 pages, 21 figures; version to match paper to appear in PR
CP violation in in the model III 2HDM
We have calculated the Wilson coefficients (i=1,2) in the
renormalization scheme in the model III 2HDM. Using the obtained
Wilson coefficients, we have analyzed the CP violation in decays (q=d,s) in the model. The CP asymmetry, , depends on the
parameters of models and in can be as large as 40% and
35% for and respectively. It can reach 4% for decays.
Because in SM CP violation is smaller than or equal to O() which is
unobservably small, an observation of CP asymmetry in the decays would unambiguously signal the existence of new physics.Comment: revtex4, 16 pages, 7 figure
Lepton Flavor Violating Process in Bi-maximal texture of Neutrino Mixings
We investigate the lepton flavor violation in the framework of the MSSM with
right-handed neutrinos taking the large mixing angle MSW solution in the
quasi-degenerate and the inverse-hierarchical neutrino masses. We predict the
branching ratio of and processes
assuming the degenerate right-handed Majorana neutrino masses. We find that the
branching ratio in the quasi-degenerate neutrino mass spectrum is 100 times
smaller than the ones in the inverse-hierarchical and the hierarchical neutrino
spectra. We emphasize that the magnitude of is one of important
ingredients to predict BR(). The effect of the deviation
from the complete-degenerate right-handed Majorana neutrino masses are also
estimated. Furtheremore, we examine the S_{3\sL}\times S_{3\sR} model, which
gives the quasi-degenerate neutrino masses, and the Shafi-Tavartkiladze model,
which gives the inverse-hierarchical neutrino masses. Both predicted branching
ratios of are smaller than the experimantal bound.Comment: Latex file, 38 pages, 10 figures, revised versio
Supersymmetric effects on Forward Backward asymmetries of
Leptonic and semi-leptonic rare decays of B-mesons are very clean (both
theoretically and experimentally) signatures of any new physics beyond the
Standard Model (SM). More specifically the decay \btokll has been theoretically
observed to be very sensitive to new physics as the Forward Backward (FB)
asymmetry in this decay mode vanishes in the SM. Supersymmetry, however,
predicts a non-vanishing value of this asymmetry. In this work we will study
the polarized lepton pair FB asymmetry, i.e. the FB asymmetry of the lepton
when one (or both) final state lepton(s) are polarized. We will study these
asymmetries both within the SM and for Supersymmetric corrections to the SM.Comment: 18 pages, RevTeX file including 21 eps figures; version accepted for
publication in Phys. Rev. D. Some references adde
Supersymmetry beyond minimal flavour violation
We review the sources and phenomenology of non-minimal flavour violation in
the MSSM. We discuss in some detail the most important theoretical and
experimental constraints, as well as promising observables to look for
supersymmetric effects at the LHC and in the future. We emphasize the
sensitivity of flavour physics to the mechanism of supersymmetry breaking and
to new degrees of freedom present at fundamental scales, such as the grand
unification scale. We include a discussion of present data that may hint at
departures from the Standard Model.Comment: 23pp. Version to appear in the EPJC special volume "Supersymmetry on
the Eve of the LHC", dedicated to the memory of Julius Wess. References and
brief discussion on collider signatures adde
Neodymium-doped cladding pumped aluminosilicate fiber laser tunable in the 0.9 micron wavelength range
A tunable high-power cladding-pumped neodymium-doped aluminosilicate fiber laser is demonstrated. The maximum power reached was 2.4 W with a slope efficiency of 41% and a threshold pump power of 1.68 W, both with respect to launched pump power, when cladding pumped by two 808 nm diode pump sources at both fiber ends. The dependence of the tuning range on the fiber length is investigated. The tuning range changed from 922 to 942 nm for a 25 m-long fiber to 908-938 nm with a 14 m-long fiber, because of reabsorption effects. The output linewidth was 0.26 nm in a diffraction-limited beam. Operation on the challenging 0.9 µm three-level transition in neodymium-doped double-clad fiber laser was facilitated by a W-type core refractive index profile. This filtered out the unwanted and competing strong transition at 1.06 µm while guidance of 0.9 µm remained intact
Fluorescence characteristics of an ytterbium-sensitized erbium-doped silica fiber for temperature sensor applications
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