No abstract

Inclusive single photon spectra have been measured in the transverse momentum (p T ) range from a few MeV/c up to approximately 1 GeV/c at various nucleon-nucleon center of momentum rapidities (y NN ) in the interval from Ϫ2.4Ͻy NN Ͻϩ0.5 in 18 GeV/c p-Be and p-W collisions. These distributions were used to estimate the inclusive p T and rapidity distributions for 0 production over approximately the same kinematic range. The measured photon spectra are compared with the expected distribution of photons from 0 decays and hadronic bremsstrahlung in order to search for new sources of ''soft'' photons at low transverse momentum. The results indicate no anomalous sources of soft photons in either p-Be or p-W interactions at these energies. The p-W data at forward angles set a limit on any excess of low p T photons at Ͻ2.65 times hadronic bremsstrahlung at the 99% C.L. ͓S0556-2813͑96͒06110-9͔