Interplay of Confinement and Decay in the Spectrum of Charmonium

Abstract

The spectrum of charmonium in the presence of a charmed-meson continuum is investigated. Radiative rates are in considerably better agreement with data than for the naive model, the largest discrepancy being a factor 2-3 for ${\ensuremath{\psi}}^{\ensuremath{'}}\ensuremath{\rightarrow}\ensuremath{\gamma}+^{3}P_{0}$. The model accounts for the peak at \ensuremath{\sim} 4.2 GeV in $\ensuremath{\sigma}(e\overline{e}\ensuremath{\rightarrow}\mathrm{had})$, and predicts a further peak at \ensuremath{\sim} 3.75 GeV due to $1^{3}D_{1}$. The latter would be the most favorable location for a charm search in $e\overline{e}$ collisions.