Evidence for direct. gamma. production at large x in psi (3100) decay

The inclusive ..gamma.. and ..pi../sup 0/ momentum spectra from psi (3100) decay have been measured in e/sup +/e/sup -/ annihilation at SPEAR. When the ..gamma.. spectrum is compared with that expected from ..pi../sup 0/ decay, an excess of high-momentum ..gamma..'s is observed. This excess is compared with that predicted by quantum chromodynamics for the decay of the psi into a ..gamma.. and two gluons.