Pulse NMR of ³He in aerogel at temperature 1.5 K

Experimental data of ³He pulse NMR in contact with aerogel (95%) in a nuclear Larmor frequency range of 5 to 20 MHz at T=1.5 K are reported. For the first time spin kinetics of ³He (adsorbed, gaseous and liquid) has been studied systematically at temperatures higher than degeneracy temperature of this quantum liquid. It has been shown, that in all cases the nuclear spin-lattice relaxation time T₁ is linearly proportional to the Larmor frequency, while the spin-spin relaxation time T₂ is frequency independent. The magnetic relaxation times T₁ and T₂ are linearly proportional to the ratio of the magnetization of whole spin system to magnetization of the adsorbed layer of ³He.