Hadronic production of charmonium in 225-GeV/<i>c</i><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msup><mml:mrow><mml:mi>π</mml:mi></mml:mrow><mml:mrow><mml:mo>−</mml:mo></mml:mrow></mml:msup></mml:mrow></mml:math>Be interactions

Events in which the charmonium states $\frac{J}{\ensuremath{\psi}}$ and ${\ensuremath{\psi}}^{\ensuremath{'}}$ are produced in 225-GeV/c ${\ensuremath{\pi}}^{\ensuremath{-}}$ Be collisions have been selected with a dimuon trigger. Coincidences with detected photons have identified radiative decays from the charmonium $P$ states ($\ensuremath{\chi}$) to the $\frac{J}{\ensuremath{\psi}}$. The fraction of $\frac{J}{\ensuremath{\psi}}$'s resulting from such decays is determined to be 0.37\ifmmode\pm\else\textpm\fi{}0.09.