B_c production at RHIC as a signal for deconfinement

The B_c meson is the bound state of bc̄ (or b̄c) whose recent detection is the first step toward completion of the spectroscopy of heavy quark mesonic states. The b-c states have properties that conveniently fill the gap between the J/ψ and the γ states. Thus it is probable that at RHIC the B_c mesons will serve as a probe of deconfined matter. We find that significant differences arise for B_c formation in deconfined and confined matter. Our initial calculations suggest that: (a) The rates of normal hadronic production mechanisms at RHIC energies are not sufficient to produce a detectable number of B_c mesons. (b) If a region of deconfined quarks and gluons is formed, the production (and survival) rate can be enhanced by several orders of magnitude. (c) The observation of B_c mesons at RHIC would signal a source of deconfined charmed quarks, and the rate of B_c production will be a measure of the initial density and temperature of that source.