Mixing of $\eta -{\eta }^{\mathrm{\prime }}$ in charge-exchange reactions and decays of mesons with heavy quarks

Involving of elastic rescattering and annihilation of quark-antiquark pairs in a final state allows us to explain a dependence of ratio for cross sections of ${\eta }^{\mathrm{\prime }}$ and $\eta$ mesons versus transfer momentum in charge exchange reactions. We estimate the mixing angle of mesons with isoscalar states of $\bar{u}u+\bar{d}d$ and $\bar{s}s$ of hidden strangeness. The evaluation includes the consistent description of yield ratio for ${\eta }^{\mathrm{\prime }}$ and $\eta$ mesons in decays of $B^0$, $B_s^0$ and $J\mathrm{/}\psi$ mesons.