POLARIMETRY ON DENSE SAMPLES OF SPIN-POLARIZED HE-3 BY MAGNETOSTATIC DETECTION

A very sensitive low-field fluxgate magnetometer is used to detect the static magnetic field produced by dense samples of spin-polarized He- 3 gas contained in spherical glass cells at pressures around several b ars. The He-3 nuclear polarization can be extracted with high precisio n Delta P/P < 1% by utilizing magnetostatic detection in combination w ith adiabatic fast-passage spin reversal. The polarization losses can be kept well below 0.1% thus making this type of polarimetry almost no n-destructive. More simply even, P can be measured with reduced accura cy by the change of field when the cell is removed from the fluxgate. In this case the accuracy is limited to about 10% due to the uncertain ties about the susceptibilities of the cell walls.