Non Standard $\eta-\eta^{\prime}$ mixing and the Nonleptonic B and   $\Lambda_b$ Decays to $\eta$ and $\eta^{\prime}$
  Radial mixing in the pseudoscalar $\eta-\eta^{\prime}$ systems can be generated from hyperfine interactions and annihilation terms. For the $\eta-\eta^{\prime}$ system we find the effects of radial mixing are appreciable and seriously affect the decay branching ratios for $B \to \eta(\eta^{\prime})K(K^*)$, mainly by modifying the $B \to \eta(\eta^{\prime})$ form factors. In particular, the effect of radial mixing in conjunction with the interference effects among penguin amplitudes can resolve puzzles in the $B \to \eta(\eta^{\prime}) K$ decays. The decay $\Lambda_b \to \Lambda \eta(\eta^{\prime})$ on the other hand is dominated by a single amplitude so that the significant interference effects of B decays are absent here. Moreover, since no $\Lambda_b \to \eta(\eta^{\prime})$ form factors are involved here, the effect of radial mixing is essentially negligible. Hence, unlike the B system, we do not predict a large enhancement of $\Lambda_b \to \Lambda \eta^{\prime}$ relative to $\Lambda_b \to \Lambda \eta$. 
Alakabha Datta, Harry J. Lipkin and Patrick J. O'Donnell