摘要: New results are presented from the Lead Glass Wall experiment (SP26) at SPEAR. Motivation was due to recent Quantum Chromodynamics (QCD) calculations, for the gamma + 2 gluons decay mode of orthocharmonium, to search for direct ph... 展开 New results are presented from the Lead Glass Wall experiment (SP26) at SPEAR. Motivation was due to recent Quantum Chromodynamics (QCD) calculations, for the gamma + 2 gluons decay mode of orthocharmonium, to search for direct photons from psi(3100) decay. Inclusive gamma and pi exp 0 production from psi(3100) decay was measured using the Lead Glass Wall addition to the Mark I detector. pi exp 0 and charged pi production are compared and the pi exp 0 decay contribution to the inclusive gamma spectrum calculated. An excess of gamma 's was found which is partly explained by eta production and decay, but a signal of high energy direct photons remains. This excess of direct photons is compared with QCD predictions and previously measured radiative decays of the psi. (ERA citation 05:005076) 收起