Idealized drawing shows polarization of cobalt-60 nuclei in a magnetic field at a temperature near absolute zero. The nuclei behave as small spinning magnets whose north poles are conventionally taken to be the direction of right-handed spin. Thus, at very low temperatures, where atoms lose most of their random thermal motion, the nuclei line up in a magnetic field so that their spin axes are parallel. The experiments at NBS showed that emission of electrons in beta decay of cobalt-60 nuclei is greater in the direction of the south pole of the nucleus (pointing toward the north pole of the magnet), as indicated in the drawing.