Effect of 14N Nucleus Capture in Nuclear Quadrupole Resonance at Small Relaxation Parameters

摘要

Experiments on detecting induction signals of nuclear quadrupole resonance (NQR) on 14N nuclei in hexahydro-1,3,5-trinitro-s-triazine C3H6N6O6 (RDX) with preliminary changed population densities of NQR energy levels upon exposure to a saturating pulse are described. It is demonstrated that this actually causes the induction signal amplitude to change; however, complete saturation of the transition cannot be reached because of the NQR relaxation time. It is also demonstrated that the results of calculations without regard for the relaxation processes in RDX lack experimental support. Experimental data demonstrate the feasibility of application of the methods of preliminary change of the population densities (by pumping) for multifrequency experiments in NQR and explosive detection.