Measurement of the axial-vector to vector coupling constant, ¦g 1/f 1¦, in Σ−→ne − \bar v decay

The ratio of the axial-vector to vector coupling constant, ¦g ₁/f ₁¦, in theΣ ^?→ne ^? \(\bar v\) decay was determined from the electron-neutrino angular distribution. In a sample of 454Σ ^?→ne ^? \(\bar v\) decays a search was made for subsequent neutron proton scattering in order to detect the decay neutrons. TheΣ hyperons were produced by stoppingK ^?-mesons in the 81 cm Saclay hydrogen bubble chamber. For the kinematical analysis 33Σ ^?→ne ^? ν events with associatednp→np interactions were accepted. The value ¦g ₁/f ₁¦=0.37 _?0.19 ^+0.26 was obtained.