Ψ (nS) and χb (nP) production at hadron colliders in nonrelativistic QCD

Ψ(nS) and χb(nP) (n=1, 2, 3) production at the LHC is studied at next-to-leading order in αs in nonrelativistic QCD. Feeddown contributions from higher χb and Ψ states are all considered for lower Ψ cross sections and polarizations. The long distance matrix elements (LDMEs) are extracted from the yield data, and then used to make predictions for the Ψ(nS) polarizations, which are found to be consistent with the measured polarization data within errors. In particular, the Ψ(3S) polarization puzzle can be understood by a large feeddown contribution from χb(3P) states. Our results may provide a good description for both cross sections and polarizations of prompt Ψ(nS) and χb(nP) production at the LHC.