6 research outputs found
Branching Ratio and CP Asymmetry of Decays in the Perturbative QCD Approach
In this paper,we calculate the branching ratios and CP-violating asymmetries
for and B^+\to \rho^+ \etap decays in the
perturbative QCD factorization approach. In this approach, we not only
calculate the usual factorizable contributions, but also evaluate the
non-factorizable and annihilation type contributions. Besides the
current-current operators, the contributions from the QCD and electroweak
penguin operators are also taken into account. The theoretical predictions for
the branching ratios are and ,
which agree well with the measured values and currently available experimental
upper limits. We also predict large CP-violating asymmetries in these decays:
, , ,
, , and , which
can be tested by the current or future B factory experiments.Comment: 29 pages, 9 ps figures, more phenomenological discussions added,
scale dependence of computed observables are considered, typos corrected, the
figures and conclusions remain unchange
Branching Ratio and CP Asymmetry of Decays in the Perturbative QCD Approach
We calculate the branching ratios and CP-violating asymmetries for and decays in the
perturbative QCD (pQCD) factorization approach here. We not only calculate the
usual factorizable contributions, but also evaluate the non-factorizable and
annihilation type contributions. Besides the current-current operators, the
contributions from the QCD and electroweak penguin operators are also taken
into account. The pQCD results for the CP-averaged branching ratios are , , and , which agree very well with the measured values or currently
available experimental upper limits. We also predict large CP-violating
asymmetries in these decays: A_{CP}^{dir}(\pi^\pm \etap)\sim
A_{CP}^{dir}(\pi^0 \etap)\sim -0.35 , and A_{CP}^{mix}(\pi^0 \etap)\sim
0.67, but with large errors. The pQCD prediction for ( has the same (opposite) sign with
the primary measured values. Further improvements in both theory and
experiments are needed to clarify this discrepancy.Comment: 28 pages, 8 figures, several typos correcte