Towards higher-order calculations of quarkonia production with kT - factorization: P-wave charmonia

Inclusive P-wave charmonia production in hadronic collisions at high energies is discussed in the framework of non-relativistic QCD and k(T)-factorization formalism. We present two consistent approaches to merge the usual leading order k(T)-factorization calculations with tree-level next-to-leading order off-shell amplitudes. Using these prescriptions, we extracted long-distance matrix elements for k(T) mesons from a combined fit to available Tevatron and LHC data. In contrast to previous (leading order) calculations, our fits do not rule out the equalness of the color singlet wave functions of chi c1 and chi c2 states. The extracted values of long-distance matrix elements are employed to analyse the chi c polarization data reported recently by the CMS Collaboration. Our predictions are in a reasonably good agreement with the Tevatron and LHC measurements within the theoretical and experimental uncertainties.