Critique of the method of measurement of magnetic moments of nuclei embedded in ferromagnetic foils

Anomalous magnetic fields have been found to exist at the sites of nuclei embedded, by recoil from Coulomb excitation, into iron and nickel foils, of such a nature that for considerable time intervals the large magnetic fields at the stopped nuclei are not parallel to the external magnetic fields. The reliability of this method of measuring nuclear g factors is therefore in considerable doubt. A model of the magnetic-field distribution is presented, but the mechanism which produces this distribution is not understood in detail.