NMR calibration of optical measurement of nuclear polarization in He3

We have performed precise NMR measurements in order to calibrate a standard optical technique for measuring the polarization of He3 nuclei. This optical technique requires knowledge of the pressure-dependent relationship between the nuclear polarization and the degree of circular polarization of the 668-nm light emitted from a He3 discharge. We determined the nuclear polarization by comparing the adiabatic fast-passage NMR signal from samples of polarized He3 at pressures between 0.1 and 5 torr to an identical sample of water. For water, the polarization is known from statistical mechanics. The He3 is polarized using the metastability exchange technique for optical pumping of He3. The accuracy of the calibration is 2%, which is required for applications in nuclear physics. © 1993 The American Physical Society.

Duke Scholars

Author Haiyan Gao Physics