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We study $\chi_{cJ}\to VV$ decays using the QCD effective field theoryapproach. The helicity suppressed decay amplitudes are also considered. Thecolour-singlet contributions of these amplitudes suffer from the endpointsingularities, it is shown that they can be absorbed into renormalisation ofthe nonfactorisable colour-octet matrix element. The latter can be associatedwith the colour-octet component of the charmonium wave function. The heavyquark spin symmetry makes it possible to establish the relationships betweencolour-octet matrix elements for different states $\chi_{cJ}$ up to higherorder corrections in small velocity $v$. This allows us to estimate thepolarisation parameters for $\chi_{c2}\to VV$ using data for $\chi_{c0,1}\toVV$. This analysis is carried out for the available data on the $\chi_{cJ}\to\phi\phi$ decays.

A description of $\chi_{cJ}\to VV$ decays within the effective field theory framework