The Magnetic Moments of the Neutron and the Deuteron

The magnetic moments of the neutron and the deuteron have been measured in terms of the proton moment. The radiofrequency resonance technique of Alvarez and Bloch was used to determine the Larmor frequency of neutron precession in a magnetic field in which the frequency of proton precession had been determined by the method of Purcell, Torrey, and Pound. The ratio of the magnetic moment of the neutron to the magnetic moment of the proton is 0.68479±0.0004. The ratio of the deuteron moment to the proton moment is 0.30702±0.0001, in agreement with the Columbia value. Taking the magnetic moment of the proton as 2.7896 nuclear magnetons, the neutron moment is -1.9103±0.0012 and the deuteron moment 0.85647±0.0003 nuclear magneton. These values lead to a prediction of an admixture of 4.0 percent ${}_{}{}^3{}_{}{}^{}D_1^{}{}_{}{}^{}$ state in the ground state of the deuteron, in agreement with the value 3.9 percent found by Rarita and Schwinger from the magnitude of the electric quadrupole moment of the deuteron. The need for further theoretical investigation of the deuteron magnetic moment is pointed out.