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 ¹²⁹Xe atoms will cause an increased relaxation rate. We measured the transverse spin relaxation time of ¹²⁹Xe verse the applied magnetic field gradient and the cell temperature. We then compared the different transverse spin relaxation behavior of dual isotopes of xenon (¹²⁹Xe and ¹³¹Xe) 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 ¹²⁹Xe 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 ¹²⁹Xe in H2 and N2 to be 0.4 ± 0.26 cm²/sec and 0.12 ± 0.02 cm²/sec. The results are close with theoretical calculation.