Magnetic octupole

E.E. Nikitin, E.I.Dashevskaya, J.Alnis, M.Auzinsh, E.Abraham, B.R.Fumeaux, M.Keil, Ch.McRaven, N.Shafer-Ray, R.Waskowsky, Predietion and measurements of the speed-dependent throughput of a magnetic octupole velocity filter including nonadiabatic effects, Phys.Rev.A 68, 023403 (2003)... 

The contributions of the magnetic octupole (M ) and the electric hexadecapole (M ) terms are always much smaller than the magnetic dipole and electric quadrupole terms and are therefore not considered here. 

L.A. Hackel, K.H. Casleton, S.G. Kukolich, S. Ezekiel, Observation of magnetic octupole and scalar spin-spin interaction in I2 using laser spectroscopy. Phys. Rev. Lett. 35, 568 (1975)... 

The experiments show that in the ground states of nuclei the electric moments of 2 order with odd I and all 2-pole magnetic moments with even I are missing. Only electric monopole, magnetic dipole, electric quadrupole, magnetic octupole, etc., moments are observed in experiments. This means that the 2-pole character unambiguously determines whether the moment is electric or magnetic, and these latter attributes may be omitted. This rule can be viewed as a consequence of a symmetry property (parity) of the nuclear states. 

JAC ea)Q <0.002 kHz magnetic octupole coupling for iodine nucleus. 

Remark The influence of the nuclear magnetic octupole hyperfine interaction is discussed in [87Ced]. 

It can be shown that, of the possible higher-order multipole moments, the nuclear magnetic moments of even order vanish because of symmetry requirements with respect to the nuclear equatorial plane. The next non-vanishing moment, the nuclear magnetic octupole moment, is very small and-will be ignored here. 

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