Single-π0 production cross-sections at THETA/sub CM/ approx. 900, 170, and 80 at the CERN ISR

We have measured the inclusive cross section for π0 production at small center of mass (CM) polar angles in an experiment conducted at the CERN Intersecting Storage Rings. The cross section is presented as a function of transverse momentum for the following values of CM polar angle (theta) and CM energy (√s): at √s = 23.3 GeV, theta approx. = 900, 220, 200, 17 1/20, and 150 with 1 < P/sub T/(GeV/c) < 2.5 - at √S = 52.8 GeV, theta approx. = 900, 220, 200, 17 1/20, 150, 120, 100, 7 1/20, and 50 with 1 < P/sub T/(GeV/c) < 4. The measured cross section is compared to two models. The black-box model of Feynman, Field, and Fox is in agreement with our results: the hypothesis of radial scaling is incompatible with them