Total cross section for p+p → p+p+π0 close to threshold

The total cross section for the reaction p+p → p+p+π0 was measured at nine center-of-mass energies from 1.5 MeV to 23 MeV above threshold. The experiment was carried out with the Indiana cooler, making use of the experimental advantages on a stored, electron-cooled beam. Over most of the covered energy range only the lowest possible angular momentum state contributes to the exit channel. The energy dependence of the total cross section close to threshold is discussed