Large CP Asymmetries in $B^{\pm }\to {\eta }_c({\chi }_{c0}){\pi }^{\pm }$ from ${\eta }_c({\chi }_{c0})$ Width

Abstract

We study CP asymmetries in $B^{\pm }\to h{\pi }^{\pm }$ decays, where the hadronic states $h=\rho \rho ,K\text{Kbar}\pi$, ${\pi }^{+}{\pi }^{-}{K}^{+}{K}^{-}$, etc., and $h={\pi }^{+}{\pi }^{-},K^{+}{K}^{-},2({\pi }^{+}{\pi }^{-})$, etc., are taken on the resonances ${\eta }_c$ and ${\chi }_{c0}$, respectively. The relatively large ${\eta }_c$ and ${\chi }_{c0}$ decay widths, of about 10$-$15 MeV, provide the necessary absorptive phase in the interference between the resonance (going through $b\to c\text{cbar}d$) and the background (through $b\to u\text{ubar}d$) contributions to the amplitude. Large asymmetries of order 10$\%$ or more are likely in some modes.

Comments: 12 pages