The ultra-cold polarized hydrogen jet project
R. S. Raymond, Donald G. Crabb, T. Roser +2 more
Research is described on a jet of polarized atomic hydrogen.Atoms in the two lower hyperfine states are trapped at 0.4 k in a 5 T magnetic field.Microwaves at 140 GHz then drive transitions to the upper hyperfine states and these atoms are expelled from the field to form the beam.Atoms have been trapped, transitions driven, and atoms detected outside the trapping field, but preliminary measurements are not fully understood.Studies are continuing.Work is continuing to test the applicability of cryogenic atomic physics techniques to the production of dense polarized atomic hydrogen beams.At high magnetic fields (5 T) and low temperatures (0.5 k), the magnetic energy of a hydrogen atom, approximately #, • B, is considerably higher than the thermal energy, kT.When cold atoms approach a high magnetic field, atoms in the two upper hyperfme states see a potential hill and are repulsed.Atoms in the two lower hyperfine states see a potential well, are attracted in, thermalize by hitting cold walls and are trapped.These trapped atoms are then irradiated with microwaves of the proper frequency (approximately 140 GHz for a 5 T field) to drive transition to one of the upper hyperflne states.These flipped atoms, now on a potential hill, are accelerated out of the field to form the beam.
AIP conference proceedings•Jan 1, 1989•0 citations