Inclusive measurements of the pp→pnπ+ reaction at 420 and 500 MeV

Inclusive measurements of the pion differential cross sections and analyzing powers have been carried out for the pp-->pn pi(+) reaction at 420 and 500 MeV using the SASP spectrometer at TRIUMF. Pion energies from the onset of the continuum down to about 25 MeV were covered in the angular range from 23 degrees to 100 degrees (lab). Total cross sections of 0.750+/-0.075 mb and 2.77+/-0.28 mb were determined fur the pp-->pn pi(+) reaction at 420 and 500 MeV, respectively. The experimental results are presented and discussed within the framework of a partial wave analysis. Theoretical predictions from a covariant one-boson-exchange model that includes final state interactions, provide a good description of the data. The pion spectra, in the region corresponding to low relative np energies, are also well described by a Anal state interaction model that uses the pp-->d pi(+) cross sections as input. Details of the determination of the background corrections and detector efficiencies will be discussed. [S0556-2813(99)03606-7].