Colour-octet NLO QCD corrections to hadronic chi_J decays

In this paper we present a complete next-to-leading order QCD calculation of the $\chi_J$ ($^3P_J\; ;J=0,1,2$) hadronic decay width. We include the NLO colour-octet contribution, as defined in the Bodwin, Braaten and Lepage formalism. We extract an estimate of the colour-octet parameter \height\ from the charmonium decay data.