Mass of theΣ+Hyperon

Abstract

Ten examples of the protonic decay from rest of the ${\Sigma }^{+}$ hyperon have been analyzed. The ranges of the protons from the ${\Sigma }^{+}$ decays were corrected for variations in the stopping power of each emulsion batch by determining the mean range of $\mu$ mesons from $\pi -\mu$ decays. The mean range of the protons, after correcting for variations in stopping power, was found to be 1669.4±8.0 microns. The rms deviation of the proton ranges was found to be 38.5±8.0 microns. The $Q$ of the ${\Sigma }^{+}$ decay, ${\Sigma }^{+}\to p+{\pi }^0$ is 116.1±0.5 Mev, and the mass of the ${\Sigma }^{+}$ hyperon is $(2327.4\mathrm{}\pm 1.0)m_e$.