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

The presence of a magnetic field gradient in a sample cell containing spin-polarized Xe-129 atoms will cause an increased relaxation rate. We measured the transverse spin relaxation time of Xe-129 verse the applied magnetic field gradient and the cell temperature. We then compared the different transverse spin relaxation behavior of dual isotopes of xenon (Xe-129 and Xe-131) 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 Xe-129 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 Xe-129 in H-2 and N-2 to be 0.4 +/- 0.26 cm(2)/sec and 0.12 +/- 0.02 cm(2)/sec. The results are close with theoretical calculation.