605 research outputs found
General analysis of the rare Bc->D^*_s l^+ l^- decay beyond the standard model
The general analysis of the rare Bc->D^*_s l^+ l^- decay is presented by
using the most general, model independent effective Hamiltonian. The
dependencies of the branching ratios, longitudinal, normal and transversal
polarization asymmetries for l^- and the combined asymmetries for l^- and l^+
on the new Wilson coefficients are investigated. Our analysis shows that the
lepton polarization asymmetries are very sensitive to the scalar and tensor
type interactions, which will be very useful in looking for new physics beyond
the standard model.Comment: 27 Pages, 14 Figure
B--> K^* l^+ l^- decay in the two Higgs doublet model with flavor changing neutral currents
We study the decay width, forward-backward asymmetry and the longitudinal
lepton polarization for the exclusive decay B --> K^* l^+ l^- in the two Higgs
doublet model with three level flavor changing neutral currents (model III) and
analyse the dependencies of these quantities on the the selected parameters,
\xi^{U,D}, of model III including the next to leading QCD corrections. It is
found that to look for charged Higgs effects, the measurements of the branching
ratio, forward-backward asymmetry and the longitudinal lepton polarization for
the decay B --> K^* l^+ l^- are promising.Comment: 17 pages, 6 figure
T violation in (Lambda_b -> Lambda l^+ l^-) decay beyond standard model
Using the most general, model independent form of effective Hamiltonian, the
transverse polarization P_T of Lambda in Lambda_b -> Lambda l^+ l^- decay is
studied. It is observed that the averaged is very sensitive to the
existence of new physics and can attain large values, which can be measured at
future colliders.Comment: 12 pages, 7 figures, LaTeX formatte
Screening for Ascochyta Blight Resistance in Chickpea (Cicer arietinum L.)
Ten chickpea lines CM1966/93, CMC77S, CM843/98, CM1223/98, CM1441/98, CM2070/98, CC 104/99, CC106/99, CC124/00 were found highly resistant to Ascochyta blight with disease rating of 2 followed by 34 lines that were resistant and 21 lines were tolerant. None was found immune to blight. The highly resistant lines have exhibited higher level of resistance against blight as compared to earlier released varieties (CM72, CM88 and CM2000)
The exclusive and decays in the general two Higgs doublet model
We study the differential branching ratio, branching ratio and the
forward-backward asymmetry for the exclusive and decays in the general two Higgs doublet model including
the neutral Higgs boson effects. We analyze the dependencies of these
quantities on the neutral Higgs boson contributions and the other model
parameters. We observe that two Higgs doublet model with the neutral Higgs
boson exchanges gives quite sizable contributions to these observables for both
channels we consider. Since the neutral Higgs boson exchanges are the only
source of the forward-backward asymmetry for decay,
which is at the order of magnitude , measurement of this observable is
promising to determine the neutral Higgs boson effects.Comment: 27 pages, 18 eps figures, requires JHEP3.cls (included), replaced
with the version to appear in JHE
Leading logarithmic QCD corrections to the B_s --> \gamma \gamma decays in the two Higgs doublet model
We calculate the leading logarithmic QCD corrections to the decay B_s -->
\gamma \gamma in the two Higgs doublet model (2HDM) including O_7 type long
distance effects and estimate the restrictions of the 2HDM parameters, tan\beta
and m_H, using the experimental data of B --> X_s \gamma decay provided by the
CLEO collaboration. A lower bound for the charged Higgs mass m_H as a function
of the renormalization scale \mu is given for 2HDM model II. We further present
the dependencies of the branching ratio Br(B_s --> \gamma \gamma) and the ratio
|A^{+}|^2/|A^{-}|^2 on m_H and tan\beta including leading logarithmic QCD
corrections. The dependence on the renormalization scale is found to be strong
for both ratios. An additional uncertainty arises from the variation of the
parameters of the bound state model, (m_b, \bar{\Lambda}_s). We see, that to
look for charged Higgs effects the measurement of the branching ratio Br(B_s
--> \gamma \gamma) is promising.Comment: 25 pages, 19 figures (required epsf.sty
Analysis of B_s->\phi \ell^+ \ell^- decay with new physics effects
The rare B_s-> \phi \ell^+ \ell^- decay is investigated by using the most
general model independent effective Hamiltonian for . The
calculated Br(B_s \rar \phi \mu^+ \mu^-) = 1.92 \times 10^{-6} is in
consistent with the experimental upper bound. The dependencies of the branching
ratios and polarization asymmetries of leptons and combined lepton-antilepton
asymmetries on the new Wilson coefficients are presented. The analysis shows
that the branching ratios and the lepton polarization asymmetries are very
sensitive to the scalar and tensor type interactions. The results obtained in
this work will be very useful in searching new physics beyond the standard
model.Comment: 28 pages, 14 figure
Model independent analysis of 'Lambda' baryon polarizations in (Lambda_b -> Lambda l^+ l^-) decay
We present the model independent analysis of baryon polarizations
in the (Lambda_b -> Lambda l^+ l^-) decay. The sensitivity of the averaged
'Lambda' polarizations to the new Wilson coefficients is studied. It is
observed that there exist certain regions of the new Wilson coefficients where
the branching ratio coincides with the standard model prediction, while the
'Lambda' baryon polarizations deviate from the standard model results
remarkably.Comment: 19 pages, 9 figures, LaTeX formatte
Screening for Ascochyta blight resistance in chickpea (Cicer arietinum L.)
Ten chickpea lines CM1966/93, CMC77S, CM843/98, CM1223/98, CM1441/98, CM2070/98, CC 104/99, CC106/99, CC107/99, CC124/00 were found highly resistant to Ascochyta blight with disease rating of 2 followed by 34 lines that were resistant and 21 lines were tolerant. None was found immune to blight. The highly resistant lines have exhibited higher level of resistance against blight as compared to earlier released varieties (CM72, CM88 and CM2000)
Rare B -> K^* l^+ l^- decay, two Higgs doublet model, and light cone QCD sum rules
The decay width, forward-backward asymmetry and lepton longitudinal and
transversal polarization for the exclusive K^* -> l^+ l^- decay in a two Higgs
doublet model are computed. It is shown that all these quantities are very
effective tools for establishing new physics.Comment: 18 pages, 7 figures, LaTeX formatte
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