Abstract
3 He was polarized by the spin-exchange optical pumping (SEOP) method. The 3 He polarization measured by neutrons was compared to the value obtained by cross calibration with a thermal water signal via nuclear magnetic resonance (NMR). The neutron scattering experiments were performed at a three-dimensional neutron depolarization spectrometer (NDS) based on the design of the instrument labeled LAP-ND of FRJ-2, Germany, constructed and commissioned at the W-3 port of the Tsing Hua Open-Pool Reactor (THOR), Taiwan. The two methods show a reasonable consistency regarding the 3 He polarization. This suggests that the NMR method is convenient and reliable for testing the 3 He polarization before neutron scattering experiments are performed. © 2009 THE PHYSICAL SOCIETY OF THE REPUBLIC OF CHINA.