χcJ polarizations at the Fermilab Tevatron

Abstract

We propose the measurement of χ cJ polarizations at high energy hadron colliders to study heavy quarkonium production mechanism. We find that the color-singlet model in the k t factorization approach predicts very different behavior for χ cJ polarizations at the Fermilab Tevatron compared with the NRQCD predictions in the collinear parton model. In the color-singlet k t factorization approach, for both χ c1 and χ c2 productions, the helicity h=0 states dominate over other helicity states at large p T . These properties are very useful in distinguishing between the two production mechanisms which are related to the interesting issue of Jψ and ψ′ polarizations, and may provide a crucial test for the k t factorization approach.