Edge enhancement observed with hyperpolarized He-3

We have produced one-dimensional (1-D) magnetic resonance images of hyperpolarized He-3 in square glass cells and demonstrated edge enhancement of the signal intensity near the parallel impermeable boundaries. The size and position of the edge-enhancement peaks approximately agrees with the theoretical prediction based on solutions of the 1-D Torrey equation with boundary conditions. Additional distortion in our images is due to the long-range dipole fields produced by the polarized spins and by the bulk magnetic susceptibility of the glass. Our experiments, done in an applied field of H-0 = 31 G, demonstrate the low-field imaging capacity of hyperpolarized noble gases.