Leptonic Decay Of Lambda And Sigma Hyperons - Analysis Of Photographs - Beam And Run

Summary  A systematic search for leptonic decays of Λ0 and Σ− hyperons has been carried out in a I meter heavy-liquid bubble chamber. 8Λ β 0 and no Λ α 0 or Σβα have been found. The total number of Λ0 was ∼3 200. After correction for detection efficiency, this gives for the branching ratioρ=N(Λ β 0 )/N(Λ tot 0 )=(0.29 −12 +15 %). This seems definitely in disagreement with the simple extension of theV-A theory to this type of strangeness-nonconserving decay.