Correlated a_c ⁺a_c ^- production in e⁺e^- annihilations at √s-10.5 GeV

Using 13.6 fb^-1 of continuum two-jet e⁺e^-→cc events collected with the CLEO detector, we have searched for baryon number correlations at the primary quark level. We have measured the likelihood for a A_c ⁺ charmed baryon to be produced in the hemisphere opposite a A_c ^- relative to the likelihood for a A_c ^- charmed baryon to be produced opposite an anticharmed meson D; in all cases, the reconstructed hadrons must have momentum greater than 2.3 GeV/c. We find that, given a A_c ^- (reconstructed in five different decay modes), a Ac+ is observed in the opposite hemisphere (0.72±0.11)% of the time (not corrected for efficiency). By contrast, given a D in one hemisphere, a A_c ⁺ is observed in the opposite hemisphere only (0.21 ±0.02)% of the time. Normalized to the total number of either A_c ^- or D "tags," it is therefore 3.52±0.45±0.42 times more likely to find a A_c ⁺ opposite a A~ than a D meson. This enhancement is not observed in the JETSET 7.3 e⁺e^-→cc Monte Carlo simulation.