Measurement of theΣ+Magnetic Moment Using the Reactionγ+p→Σ++K0Near Threshold

The sample of 51 high-information $\Sigma p$ events has a mean rotation of 32° per event and gives no evidence of bias; it yields ${\mu }_{{\Sigma }^{+}}=+3.0\mathrm{}\pm 1.2{\mu }_N$ and $\alpha \overline{P}=+0.85\mathrm{}\pm 0.25$ in the direction ${\hat{P}}_{\gamma }\times {\hat{P}}_{\Sigma }$. All magnetic field components along the path of each ${\Sigma }^{+}$ have been considered. The use of nuclear emulsion enables one to include the effects of the $\Sigma p$ c.m. angle on detection efficiency, and thereby on the calculated value of ${\mu }_{{\Sigma }^{+}}$.