Measurement of the pp→ppπ0 reaction at 850 MeV/c and partial wave cross sections

A stack of annular detectors made of high purity germanium was used to measure pp-->pppi(0) differential cross sections at a beam momentum of 850 MeV/c. A total cross section of sigma=9.1+/-1.1 mub is deduced. The fitted distribution of different partial waves to the world total cross section data and to the present differential cross sections favors an approach without low-energy approximations, with the standard value for the final state interaction scattering length, and an important contribution from an intermediate NDelta state.