Transverse spin relaxation and diffusion-constant measurements of spin-polarized 129Xe nuclei in the presence of a magnetic field gradient

摘要

The presence of a magnetic field gradient in a sample cell containing spin-polarized (129)Xe atoms will cause an increased relaxation rate. We measured the transverse spin relaxation time of (129)Xe verse the applied magnetic field gradient and the cell temperature. We then compared the different transverse spin relaxation behavior of dual isotopes of xenon ((129)Xe and (131)Xe) due to magnetic field gradient in the same cell. The experiment results show the residual magnetic field gradient can be measured and compensated by applying a negative magnetic gradient in the sample cell. The transverse spin relaxation time of (129)Xe could be increased 2-7 times longer when applying an appropriate magnetic field gradient. The experiment results can also be used to determine the diffusion constant of (129)Xe in H2 and N2 to be 0.4 ± 0.26 cm(2)/sec and 0.12 ± 0.02 cm(2)/sec. The results are close with theoretical calculation.