The Specific Charge of the Positron

Previous measurements of the specific charge of beta-particles have been supplemented to include data on positrons by making a direct comparison between electrons and positrons. The positrons and electrons were obtained from artificially radioactive copper. Comparisons were made for beta-particles having approximately the velocity $\beta =0.72\mathrm{}$. The results indicate that the ratio $\frac{e}{m_0}$ for positrons is the same as for electrons within an error of approximately two percent.