Experimental Limit to the Electric Dipole Moment of the Neutron

Abstract

An experimental measurement of the electric dipole moment of the neutron by a neutron-beam magnetic resonance method is described. The result of the experiment is that the electric dipole moment of the neutron equals the charge of the electron multiplied by a distance $D=(\ensuremath{-}0.1\ifmmode\pm\else\textpm\fi{}2.4)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}20}$ cm. Consequently, if an electric dipole moment of the neutron exists and is associated with the spin angular momentum, its magnitude almost certainly corresponds to a value of $D$ less than 5\ifmmode\times\else\texttimes\fi{}${10}^{\ensuremath{-}20}$ cm.