9,745 research outputs found
The T2K Indication of Relatively Large theta_13 and a Natural Perturbation to the Democratic Neutrino Mixing Pattern
The T2K Collaboration has recently reported a remarkable indication of the
\nu_\mu -> \nu_e oscillation which is consistent with a relatively large value
of \theta_{13} in the three-flavor neutrino mixing scheme. We show that it is
possible to account for such a result of \theta_{13} by introducing a natural
perturbation to the democratic neutrino mixing pattern, without or with CP
violation. A testable correlation between \theta_{13} and \theta_{23} is
predicted in this ansatz. We also discuss the Wolfenstein-like parametrization
of neutrino mixing, and comment on other possibilities of generating
sufficiently large \theta_{13} at the electroweak scale.Comment: RevTeX 8 page
Can the Lepton Flavor Mixing Matrix Be Symmetric?
Current neutrino oscillation data indicate that the 3x3 lepton flavor mixing
matrix V is likely to be symmetric about its V_{e3}-V_{\mu 2}-V_{\tau 1} axis.
This off-diagonal symmetry corresponds to three pairs of {\it congruent}
unitarity triangles in the complex plane. Terrestrial matter effects can
substantially modify the genuine CP-violating parameter and off-diagonal
asymmetries of V in realistic long-baseline experiments of neutrino
oscillations.Comment: RexTex 14 pages (4 PS figures). More discussions adde
Annihilation Type Radiative Decays of Meson in Perturbative QCD Approach
With the perturbative QCD approach based on factorization, we study the
pure annihilation type radiative decays and . We find that the branching ratio of is
, which is too small to be measured
in the current factories of BaBar and Belle. The branching ratio of is , which is just
at the corner of being observable in the factories. A larger branching
ratio is also predicted.
These decay modes will help us testing the standard model and searching for new
physics signals.Comment: 4 pages, revtex, with 1 eps figur
Is the Cabibbo-Kobayashi-Maskawa Matrix Symmetric at the GUT Scale?
By use of the one-loop renormalization group equations and current
experimental data, we study the off-diagonal asymmetries of the
Cabibbo-Kobayashi-Maskawa (CKM) matrix at the GUT scale in the framework of the
standard model as well as its two Higgs and supersymmetric extensions. It is
concluded that the possibility of a symmetric CKM matrix at the GUT scale has
almost been ruled out.Comment: Latex 6 pages plus PS 2 pages. This tiny work would not have been put
into this archive if I had not noticed an interesting work by P. Kielanowski
et al (hep-ph/9703292), whose conclusion seems to be opposite to mine.
(Accepted for publication in J. Phys. G
More Straightforward Extraction of the Fundamental Lepton Mixing Parameters from Long-Baseline Neutrino Oscillations
We point out the simple reversibility between the fundamental neutrino mixing
parameters in vacuum and their effective counterparts in matter. The former can
therefore be expressed in terms of the latter, allowing more straightforward
extraction of the genuine lepton mixing quantities from a variety of
long-baseline neutrino oscillation experiments. In addition to the
parametrization-independent results, we present the formulas based on the
standard parametrization of the lepton flavor mixing matrix and give a typical
numerical illustration.Comment: RevTex 10 pages. Minor changes. Phys. Rev. D in printin
Summary of the NOW'98 Phenomenology Working Group
Summary of the Phenomenology Working Group at the Europhysics Neutrino
Oscillation Workshop (NOW'98), 7-9 September 1998, Amsterdam.Comment: 66 page
Testing 3+1 and 3+2 neutrino mass models with cosmology and short baseline experiments
Recent results from short--baseline neutrino oscillation experiments and
Cosmic Microwave Background anisotropy measurements suggest the presence of
additional sterile neutrinos. In this paper we properly combine these data sets
to derive bounds on the sterile neutrino masses in the 3+1 and 3+2 frameworks,
finding a potentially good agreement between the two datasets. However, when
galaxy clustering is included in the analysis a tension between the oscillation
and cosmological data is clearly present
Effects of Chinese materia medica-fuboa danggui jiao on experimental endometriosis
The objective of this paper was to investigate the effects of a Chinese Materia Medica variant -Fubao Danggui Jiao (FDJ)-on experimental endometriosis. An endometriosis model was created by virtue of auto-transplantation of endometrial tissue onto rats’ abdominal walls. The implants were allowed to grow for 30 days until the successful completion of the model. After that, forty endometriotic rats were randomly divided into four study groups and given different treatments: (1) negative control group (water, 2ml/kg, per os); (2) FDJ-A group (FDJ, 2ml/kg, per os); (3) FDJ-B group (FDJ, 4ml/kg, per os); (4) Danazol group (70mg/kg, per os). After 30 days with treatments, the volumes of endometriotic implants in each rat were measured. The implants and normal uterine horns were removed for routine histological examination. FDJ caused significant decreases in volumes of the surviving endometriotic implants, with two different doses having statistically equivalent effects. Upon histological examination, FDJ was observed to cause regression of epithelium and stroma of endometriotic implants. FDJ had revealed promising therapeutic effects on endometriosis.Keywords: Fubao Danggui Jiao; Chinese Materia Medica; Endometriosis; Danazol.Non-standard Abbreviations: Fubao Danggui Jiao - FD
- …