Search for ΔQ=−ΔS transitions in Σ-hyperon decays

Abstract

In a sample of 106Σ+ hyperons we have searched for the decaysσ+→ ne+ν andσ+→nμ+ν, which would violate theΔQ=ΔS rule. NoΣ+→ne+ν decay was found, whereas 313σ−→ne−ν decays were identified in the same film. With 90% confidence we obtain $$\frac{{\Gamma (\sum ^ + \to ne^ + v)}}{{\Gamma (\sum ^ - \to ne^ - \bar v)}} \leqq 3.10^{ - 2} .$$