Nuclear spin-lattice relaxation attenuation coefficients for use in on-line nuclear orientation experiments

The on-line low temperature nuclear orientation facility NICOLE

“…At temperatures ranging from 6.5 mK to about 100 mK and in an external magnetic field of 0.1 T, the Korringa constant for 62 Cu in Fe was found to be C K [ 62 Cu]=4.34 (25) sK. The effect of including the relaxation time into the analysis of the temperature dependence of the beta emission anisotropy is illustrated in figure 6, where the data are fitted by a theoretical curve with (left) and without (right) the correction for relaxation.…”

“…In the case that the nuclear lifetime is comparable with the cooling time, some fraction of the nuclei decay before reaching the lattice temperature so that the average nuclear orientation, as measured by the angular distribution of radioactive decay products from the oriented nuclei, is attenuated. Thus determination of the relaxation time, which increases at lower temperature, is of a vital importance in planning and conducting on-line orientation experiments as it limits the life-time of implanted nuclei which can be studied [24,25]. At a more fundamental level, nuclear spin-lattice relaxation rates of implanted elements in metals permit critical test of electronic band structure theory as they depend sensitively on the local density of states near the Fermi surface.…”

“…At a more fundamental level, nuclear spin-lattice relaxation rates of implanted elements in metals permit critical test of electronic band structure theory as they depend sensitively on the local density of states near the Fermi surface. The relaxation rate is determined by a single host/ nuclear parameter, the Korringa constant C K , and the lattice temperature T L [24,25].…”

“…49 Sc]=(+)5.616 (25) μ N [13] made the Sc isotopic chain the first for which a full set of moment measurements exists between two major shells. In addition the result completes the isotonic sequence of ground-state moments of nuclei with an odd number of f 7/2 protons coupled to a closed subshell of f 7/2 neutrons.…”

Magnetic moment ofAg104mand the hyperfine magnetic field of Ag in Fe using nuclear magnetic resonance o

“…Owing to the rather long half-life of both isotopes and their rather large magnetic hyperfine interaction strengths T int = |µB/k B I |, that is, T int 13 mK for 104 Ag g and T int 30 mK for 104 Ag g , relaxation of the nuclear spins to thermal equilibrium was sufficiently fast and no problems with incomplete spin-lattice relaxation [28][29][30] were expected.…”