Determination of $\chi_b$ spin in the decays $\chi_{b0,2}\to\psi\psi$   and $\chi_{b0,2}\to\JP\JP\to 2(\mu^+\mu^-)$
  The decays $\chi_{b0,2}\to\psi\psi$ and $\chi_{b0,2}\to\psi\psi\to2(\mu^+\mu^-)$ are considered. It is shown that with the help of $\psi$-meson angular distributions and the distributions by final muon kinematical variables it is possible to determine the spin of the decaying $\chi_b$-meson. These distributions can also give an additional information about $\psi$-meson wave functions. 
A. V. Luchinsky