Differences between proton- and pi --induced production of the charmonium chi states.

The charmonium chi states are observed in both ..pi../sup -/ and p Be interactions near 200 GeV/c via their radiative decay into J/psi. The chi(3510) and chi(3555) are produced with roughly equal cross sections in ..pi../sup -/ collisions while the chi(3555) dominates in p collisions. Simple gluon fusion can account for chi production with incident protons but additional mechanisms are needed for incident ..pi../sup -/.