Measurement of the Electron Asymmetry in the Beta Decay of Polarized<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msup><mml:mrow><mml:mi>Σ</mml:mi></mml:mrow><mml:mrow><mml:mo>−</mml:mo></mml:mrow></mml:msup></mml:mrow></mml:math>Hyperons

We report the results of a Fermilab Tevatron experiment using a ${\ensuremath{\Sigma}}^{\ensuremath{-}}$ beam with a measured polarization of 0.22 \ifmmode\pm\else\textpm\fi{} 0.04. We find the electron asymmetry in ${\ensuremath{\Sigma}}^{\ensuremath{-}}$ beta decay to be ${\ensuremath{\alpha}}_{e}=\ensuremath{-}0.53\ifmmode\pm\else\textpm\fi{}0.14$ on the basis of a sample of 25 000 events, in agreement with the Cabibbo model and in contradiction with previous experiments. The corresponding value for the ratio of axial-vector to vector form factors is $\frac{{g}_{1}}{{f}_{1}}=\ensuremath{-}0.29\ifmmode\pm\else\textpm\fi{}0.07$.