Wall relaxation of He-3 in spin-exchange cells - art. no. 143004

The He-3 longitudinal spin-relaxation rate T-1(-1) is crucial for productio n of highly polarized He-3 by spin-exchange optical pumping. We show that T -1(-1) is increased by a factor of 2-20 solely by exposure of spin-exchange cells to a few-kG magnetic field. The original T-1(-1) can be restored by degaussing the cell. The effect is attributed to magnetic surface sites and has been observed in both Pyrex and aluminosilicate-glass cells. Our resul ts both advance the understanding of wall relaxation and demonstrate the us e of He-3 as an extremely sensitive probe of surface magnetism.