2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/43503The non-$D \bar D$ decays of the $\ppp = ψ(3770)$ resonance are reviewed and possibilities for further measurements are noted. These decays can shed light on S--D mixing, the ``missing'' $ψ' = ψ(3686)$ decays, a possible discrepancy between the total and $D \bar D$ cross sections at the $\ppp$, and rescattering effects contributing to enhanced $b \to s$ penguin amplitudes in $B$ meson decays.17 pages, 3 figures. Submitted to Physical Review D. Small changes in text; references added and updatedHigh Energy Physics - Phenomenologytext