$\left|\frac{g_A}{g_V}\right|$ in the Decay ${\Sigma }^{-}\to n{e}^{-}\overline{\nu }$

The decay ${\Sigma }^{-}\to n{e}^{-}\overline{\nu }$ was studied using a hyperon beam at the Brookhaven alternating-gradient synchrotron. The ${\Sigma }^{-}$ and $e^{-}$ momenta were measured by magnetic spectrometers with magnetostrictive wire spark chambers. A threshold Cherenkov counter and a total-absorption calorimeter identified the electron and neutron, respectively. From a sample of 3507 reconstructed events we have found $\left|\frac{g_A}{g_V}\right|=0.435\mathrm{}\pm 0.035$.