Branching Ratio and CP Asymmetry of $B_s\to {\pi }^0{\eta }^{(\prime )}$ Decays in the perturbative QCD Approach

Abstract

We calculate the branching ratios and CP-violating asymmetries for $B_s^0\to {\pi }^0{\eta }^{(\prime )}$ 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. The pQCD predictions for the CP-averaged branching ratios are $BR(B_s^0\to {\pi }^0\eta )\approx 0.86\times 10^{-7}$ and $BR(B_s^0\to {\pi }^0{\eta }^{\prime })\approx 1.86\times 10^{-7}$. The pQCD predictions for the CP-violating asymmetries are $A_{CP}^{dir}({\pi }^0\eta )\sim -4.5$, $A_{CP}^{dir}({\pi }^0{\eta }^{\prime })\sim -9.1$, $A_{CP}^{mix}({\pi }^0\eta )\sim -0.2$, and $A_{CP}^{mix}({\pi }^0{\eta }^{\prime })\sim 27.0$ but with large errors. The above pQCD predictions can be tested in the near future LHC-b experiments at CERN and the BTeV experiments at Fermilab.

Comments: 15 pages 3 eps figures