Nuclear spins and moments,

Nuclear spins and moments of ground and isomeric states are basic properties probing the structure and shape of atomic nuclei. The systematic experimental study of these quantities along isotopic and isotonic chains thus allows a mapping of the nuclear behaviour, to be compared with the predictions of different nuclear models. 

During the late 1950 s and first part of the 60 s Ingvar made major contributions to our knowledge of spins and electromagnetic moments of nuclear ground and excited states. In the 1965 edition of the Bible of nuclear spectroscopy, Alpha-, Beta- and Gamma-ray Spectroscopy , Editor K.Siegbahn, he contributed an exhaustive table of nuclear spins and moments, obtained with various techniques. 

I. Lindgren, Table of Nuclear Spins and Moments, In Alpha-, Beta-, and Gamma-Ray Spectroscopy, Ed. K. Siegbahn, North Holland Publ. Comp. Amsterdam 1965. 

I. Lindgren, Nuclear Spins and Moments of Radioactive Isotopes Investigated by an Atomic Beam Method, Thesis of Doctor of Philosophy, Uppsala University, May 21 1959. 

In addition to the nuclear spins and moments discussed above, hfs experiments may also provide a direct measure of nuclear g-factors through their interacrion with an external magnetic field. Combined with experimental A-factors, one gets in this case infmmation on the differential hypeifine anomaly A, defined by ... 

Thermal atomic beams have been used extensively to determine nuclear spins and moments by investigations of the atomic hyperfine structure. The atomic-beam magnetic resonance (ABMR) method has already become classical [2]. More recent efforts include laser spectroscopy in a crossed-beam geometry, in which a large supression of the Doppler width is obtained by collimation of the atomic beam. 

The combination of collinear fast-beam laser spectroscopy and P-RADOP (radiation-detected optical pumping) has been used to measure nuclear spins and moments of neutron-rich isotopes of the light alkali elements jLi [72-74] and Na [75]. Here, the optically pumped fast atomic beam is implanted into a single crystal placed in a static magnetic field. The NMR signal is destroying the nuclear polarization detected by measuring the p-decay asymmetry. 

The nuclear spins and moments of the strongly deformed rare-earth nuclides have been discussed in detail previously within die Nilsson model in connection with the ABMR experiments mentioned above [79]. The addition of the data fiom coUinear fast-beam laser spectroscopy [48, 50, 71], the new reference values on spectroscopic quadrupole moments from muonic and pionic hfs [1], and the refined calculations within the partice-rotor model, including a number of orbitals close to the Fermi surface, have however resulted in a more complete picture and a better understanding of tiie nuclear single-particle stmcture in this region. 

The measured nuclear spins and moments of the francium isotopes have thus given detailed information on the single-particle structure and deformation along the long isotopic chain. 

Before the advent of magnetic resonance spectroscopy, nuclear spins and moments were determined almost entirely by optical spectroscopy. When a hyperfine multiplet is observed with good resolution, the value of the nuclear spin / is obtained immediately from the multiplicity, provided that / < J. In practice, the resolution has proved to be adequate for the stable isotopes of odd Z, that are all odd-proton isotopes Tb, Ho and Tm (each 100% abundant) La,... 

Selected best values of nuclear spins and moments from Table of Isotopes (Lederer and Shirley 1978) with some later data. In most cases the method identified applies only to measurements of magnetic moments (corrected for diamagnetic shielding). Values of the nuclear resonance frequency in MHz per tesla for the stable isotopes, uncorrected for diamagnetic shielding, are given in table 12. 

Fuller GH (1976) Journal of Physical and Chemical Reference Dafa-1976-5 835- -1092 Nuclear spins and moments. ... 

G.H. Fuller, V.W. Cohen Nuclear spins and moments. Nuclear Data... 

There are several references where this information has been tabulated and reference to the original work may be found. Nuclear Spins and Moments by G. H. Fuller and V. W. Cohen, Nuclear Data Tables, 5,433 (1969) contains data for all the elements. A later compilation by S. Gerstenkorn, J. Physique, 34, 55 (1973) entitled Nuclear Properties Deduced from the Optical Spectra of the Atoms, Nuclear Moments and Isotope Shift of the Actinide and Rare Earth Series, lists the data through 1973. A report Table of Nuclear Moments by V. S. Shirley and C. M. Lederer, Lawrence Berkeley Laboratory, LBL-3450 (Dec. 1974) is a listing of all the elements. They have made corrections to the magnetic dipole moments based on a revised proton moment and have also corrected for diamagnetic shielding. 

A powerful technique is to substitute atoms in the molecule with nuclei having different nuclear spins, for example deuterium (I = 1) for or (7 = j) for Examples of nuclear spins and moments are given in Table 1. The observed change in the hyperfine splitting pattern is conclusive evidence of interaction with the nucleus. 

Normal probability function, A-88 to 90 NQR, definition, 12-1 to 4 NRA, definition, 12-1 to 4 Nuclear magnetic resonance see NMR Nuclear magneton, 1-1 to 11 Nuclear spins and moments for all nuclides, 11-56 to 253 for important nuclei in NMR, 9-113 to 115 Nuclear Spins, Moments, and Other Data... 

The reduction of (11.3.7) to an approximate form involving the usual spin operators is both involved and uncertain (Appendix 4). Nevertheless, it leads to a Pauli-type Hamiltonian whose terms can be interpreted classically as field-dipole, dipole-dipole interactions and the like. This interpretation provides a basis, insecure though it may be, for a Hamiltonian when one or both particles are nuclei, provided that the nuclear spins and moments are regarded as phenomenological quantities with values to be inferred from experiment. It is then but a short step to the Hamiltonian for a many-particle system, so long as only pairwise interactions are present (as is currently believed to be the case). 

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