Tuesday, July 30, 2013

1307.7186 (Dong Xu et al.)

Large SU(3) breaking effects and CP violation in $B^+ $ decays into
three charged SU(3) octet pseudoscalar mesons
   [PDF]

Dong Xu, Guan-Nan Li, Xiao-Gang He
The LHCb collaboration has recently reported evidence for non-zero CP asymmetries in $B^+$ decays into $\pi^+ K^+ K^-,\; \pi^+\pi^+\pi^-,\; K^+ K^+ K^- $ and $K^+\pi^+\pi^-$. The branching ratios for these decays have also been measured with different values ranging from $5\times 10^{-6}$ to $51\times 10^{-6}$. If flavor SU(3) symmetry is a good symmetry for B decays, it is expected that branching ratios for the pairs with $\Delta S=0$ and $\Delta S = 1$ have, respectively, the same branching ratios and the same CP asymmetries. It is also expected that the rate asymmetries for the $\Delta S =0$ and $\Delta S =1$ decay modes to be equal in size, but different in signs. The LHCb data do not exhibit the expected pattern for the branching ratios. The rate differences for $B^+\to \pi^+\pi^+\pi^-$ and $B^+\to K^+ K^+ K^-$ satisfy the relation between $\Delta S =0$ and $\Delta S=1$ well, but the other two do not, with the CP asymmetries having different signs than expected. In this work we study SU(3) breaking effects on these decays. We find that the decay pattern can be explained by large SU(3) breaking effects.
View original: http://arxiv.org/abs/1307.7186

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