Measurement of the ratio ofΣ0toΛ0inclusive production from 28.5-GeV/cprotons on beryllium

The ratio of the cross section for ${\Sigma }^0$ inclusive production to the cross section for ${\Lambda }^0$ inclusive production has been measured with 28.5-GeV/c protons incident on a beryllium target at an average laboratory production angle of 4°. This ratio was measured to be 0.278±0.011±0.05, where the uncertainties are statistical and systematic in that order. The ratio does not depend strongly on the momentum of the produced particle between 10 and 24 GeV/c. The effect of ${\Sigma }^0$ contamination on previous determinations of the polarization of inclusively produced ${\Lambda }^0$’s is discussed.