Calculated differential π+ production spectra at large angles from 28 GeV protons on a thick iridium target and comparisons with experimental data

Calculated results of the low-energy (< 100 MeV) π+ production spectra from 28 GeV protons incident on a thick iridium target are presented and compared with experimental data. Experimental results are available at angels of 660, 900, and 1330 with respect to the incident proton beam and comparisons with calculations are given at each of these angles. The calculated and experimental results are in moderately good agreement (factor of 2-4) over the energy range considered. Calculated results of the neutron, proton, π+ and π- energy spectra, averaged over the angular interval 450 to 750, are also presented for energies <= 500 MeV. (orig.)