Complete Nonrelativistic-QCD Prediction for Prompt Double J/ψ Hadroproduction

We perform a complete study of prompt double J/psi hadroproduction at leading order in the nonrelativistic-QCD factorization framework by including all possible pairings of the c (c) over bar Fock states S-1(0)[8] S-3(1)[1,8] and P-3(J)[1,8] with J = 0, 1, 2. We find that the S-1(0)[8] and P-3(J)[8] channels of J/psi and psi' production and the P-3(J)[1] and S-3(1)[8] channels of chi(cJ) production, which have been overlooked so far, greatly dominate at large invariant masses and rapidity separations of the J/psi pair, and that their inclusion nearly fills the large gap between previous incomplete predictions within the color-singlet model and the recent measurement by the CMS Collaboration at the CERN LHC, leaving room for next-to-leading-order corrections of typical size.