Hadronic production of the new resonances: Probing gluon distributions

Assuming that the new resonances observed at 3095 and 3684 MeV are bound states of a new, heavy quark and its antiquark, we consider several models for the production of such states in hadronic collisions. The dominant mechanism by which these particles couple to other hadrons (composed of normal quarks) may be via gluons. In analogy with the Drell-Yan model for quark-antiquark annihilation into a massive virtual photon, those new particles with even charge conjugation may be regarded as produced by gluon-gluon annihilation. Thus the (presently) hypothetical $0^{-+}$ partner ${\eta }_c$ of the observed particles may serve as a short-distance probe of the gluon distributions within hadrons. We estimate the production cross section of ${\eta }_c$ in nucleon-nucleon collisions using various models for gluon distributions. In addition, estimates are made for the production of final states containing pairs of charmed hadrons in the central region.