183,646 research outputs found
Measuring |V_{td} / V_{ub}| through B -> M \nu \bar\nu (M=\pi,K,\rho,K^*) decays
We propose a new method for precise determination of |V_{td} / V_{ub}| from
the ratios of branching ratios BR(B -> \rho \nu \bar \nu ) / BR(B ->\rho l \nu
) and BR(B -> \pi \nu \bar \nu ) / BR(B -> \pi l \nu ). These ratios depend
only on the ratio of the Cabibbo-Kobayashi-Maskawa (CKM) elements |V_{td} /
V_{ub}|$ with little theoretical uncertainty, when very small isospin breaking
effects are neglected. As is well known, |V_{td} / V_{ub}| equals to (\sin
\gamma) / (\sin \beta) for the CKM version of CP-violation within the Standard
Model. We also give in detail analytical and numerical results on the
differential decay width d\Gamma(B -> K^* \nu \bar \nu ) / dq^2 and the ratio
of the differential rates dBR(B -> \rho \nu \bar \nu )/dq^2 / dBR(B -> K^* \nu
\bar \nu )/dq^2 as well as BR(B -> \rho \nu \bar \nu ) / BR(B -> K^* \nu \bar
\nu) and BR(B -> \pi \nu \bar \nu ) / BR(B -> K \nu \bar \nu).Comment: LaTeX with 2 figures, 12 page
A note on q-Bernstein polynomials
In this paper we constructed new q-extension of Bernstein polynomials. Fron
those q-Berstein polynomials, we give some interesting properties and we
investigate some applications related this q-Bernstein polynomials.Comment: 13 page
User's guide for the Nimbus 7 Scanning Multichannel Microwave Radiometer (SMMR) CELL-ALL tape
The SMMR instrument onboard the Nimbus-7 satellite has been in operation since October 1978. It provided global coverage of passive microwave observations at 6.6, 10.7, 18, 21, and 37 GHz. The oberved brightness temperature can be used to retrieve geophysical parameters, principally sea surface temperature, atmospheric water vapor and liquid water content over oceans, sea ice concentration, and snow cover over land. The SMME CELL-ALL Tape contains earth-located calibrated brightness temperature data which have been appropriately binned into cells of various grid sizes, allowing intercomparisons of observations made at different frequencies (with corresponding different footprint sizes). This user's guide describes the operation of the instrument, the flow of the data processing the calibration procedure, and the characteristics of the calibrated brightness temperatures and how they are binned. Detailed tape specifications and lists of available data are also provided
Low scale Seesaw model and Lepton Flavor Violating Rare B Decays
We study lepton flavor number violating rare B decays, , in a seesaw model with low scale singlet Majorana neutrinos
motivated by the resonant leptogenesis scenario. The branching ratios of
inclusive decays with two almost
degenerate singlet neutrinos at TeV scale are investigated in detail. We find
that there exists a class of seesaw model in which the branching fractions of and can be as large as and
within the reach of Super B factories, respectively, without being in
conflict with neutrino mixings and mass squared difference of neutrinos from
neutrino data, invisible decay width of and the present limit of .Comment: 19 pages, 6 figure
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