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Diamagnetic correction to the 9Be+ ground-state hyperfine constant



Nobuyasu Shiga, Wayne M. Itano, John J. Bollinger


We report an experimental determination of the diamagnetic correction to the 9Be+ ground state hyperfine constant A. We measured A = −625 008 837.371(11) Hz at a magnetic field B of 4.4609 T. Comparison with previous results, obtained at lower values of B (0.68 T and 0.82 T), yields the diamagnetic shift coefficient k = 2.63(18) × 10−11 T−2, where A(B) = A0 × (1 + kB2). The zero-field hyperfine constant A0 is determined to be −625 008 837.044(12) Hz. The g-factor ratio gI'/gJ is determined to be 2.134 779 852 7(10) × 10−4, which is equal to the value measured at lower B to within experimental error. Upper limits are placed on some other corrections to the Breit-Rabi formula. The measured value of k agrees with theoretical estimates.
Physical Review A


atomic structure, Breit-Rabi formula, diamagnetic correction, electron spin flip resonance, ESR, hyperfine constant, Penning trap


Shiga, N. , Itano, W. and Bollinger, J. (2011), Diamagnetic correction to the <sup>9</sup>Be<sup>+</sup> ground-state hyperfine constant, Physical Review A, [online],, (Accessed June 14, 2024)


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Created July 21, 2011, Updated January 3, 2024