Experiment on Charge Independence in Interactions of Nucleons and Pions

The ratio ($R$) of the differential cross sections of the reactions $p+d\to {\mathrm{H}}^3+{\pi }^{+}$ and $p+d\to {\mathrm{He}}^3+{\pi }^0$ has been measured at a bombarding energy $E_p=591\mathrm{}$ Mev. The ${\mathrm{He}}^3$ and ${\mathrm{H}}^3$ nuclei are detected by the combination of magnetic deflection, time-of-flight measurement and pulse-height selection. The results are $R=2.26\mathrm{}\pm 0.11, 2.10\pm 0.14, \mathrm{and} 2.05\pm 0.09$ at c.m. angles of the heavy particles of 52°, 67°, and 143°, respectively. The agreement with the predictions of charge independence is satisfactory when the Coulomb and mass corrections are taken into account.