Medium field rf transitions for polarized beams of hydrogen and deuterium

A medium field rf transition unit (MFT) which can induce one or a sequence of transitions between adjacent hyperfine states (|Δm_f| = 1) of hydrogen and deuterium has been constructed and tested. The tests were carried out by ionizing atoms from an atomic beam source after the MFT and determining the vector and tensor polarizations of the proton and deuteron beams. The measured polarizations were found to be (96 ± 1)% of the calculated maximum for hydrogen and (96 ± 3)% for deuterium. The versatility of the MFT makes it possible to produce tensor or vector polarized deuterium beams with the largest figure of merit (P²I) as well as hydrogen beams in a pure spin state using only three rf transition units. The measured polarization of the beam is P_zz = +0.91 ± 0.02 and P_zz = -1.75 ± 0.04 for tensor polarized deuterium and P_z = +0.92 ± 0.02 and P_z = -0.95 ± 0.02 for vector polarized deuterium. Hydrogen atoms in a pure spin state were produced with P_z = +0.92 ± 0.01 and P_z = -0.88 ± 0.01.