Crampton, S. B.Berg, HowardRobinson, H. G.Ramsey, Norman2014-05-281970Crampton, S. B., H. C. Berg, H. G. Robinson, and N. G. Ramsey. 1970. Determination of the Quadrupole Coupling Constant in the N^{14} Atomic Ground State. Physical Review Letters 24, no. 5: 195–197.0031-90071079-7114http://nrs.harvard.edu/urn-3:HUL.InstRepos:12220370The zero-field hyperfine frequencies in the ground state of atomic N14 have been measured in a hydrogen maser with sufficient accuracy to resolve the quadrupole coupling constant B. The result is B=+1.32±0.20 Hz.en-USJournal Article2014-05-2810.1103/PhysRevLett.24.195