AMPLITUDES OF GAMMA-DETECTED NMRON SPIN-ECHO SIGNALS

The amplitudes of the spin echo and the baseline components of gamma detected NMRON signals have been calculated for the pure Zeeman case using a density matrix approach. Optimum turn angles and the separate and combined influences of line broadening and skin effect, appropriate to bulk ferromagnetic metals, are examined. For narrow line, zero skin effect samples, the triple pulse sequence (cos-1(1/square-root3)) - 180-degrees - (180-degrees - cos-1(1/square-root3)) affords the largest principal echo. However, its advantage is diminished with the introduction of either line broadening or skin effect and is subsequently lost when both these effects are included or either becomes severe. The skin effect distortion of the spin echo signal can dominate over intermediate-to-broad line distortions, for that range of experimental conditions generally applicable to metallic ferromagnetic hosts.