π+−pInteractions at 500 Mev

The interaction of ${\pi }^{+}$ mesons with protons at an energy of 500 Mev has been studied in a hydrogen bubble chamber. Phase-shift analyses with $S$ and $P$ waves were made, and a near degeneracy was found between the Fermi and Yang solutions. When $D$ waves were included, an additional ambiguity was found. The $D$-wave phase shifts are small, but they have a considerable effect on the other phase shifts. The cross section for single pion production is 2.85±0.5 mb. The ratio $\frac{\mathrm{}(p+0\mathrm{})\mathrm{}}{\mathrm{}(n++)\mathrm{}}$ is ${1.5}_{-0.5\mathrm{}}^{+1.5\mathrm{}}$. The cross section leading to $p++-$ was found to be of the order of 30 μb.