RF transition systems for the Triangle Universities Nuclear Laboratory atomic beam polarized ion source

A system of compact radio-frequency transitions, consisting of two medium-field units and a single strong-field unit, has recently been installed and tested in the atomic-beam polarized ion source at the Triangle Universities Nuclear Laboratory. With care and proper tuning, this new system provides deuteron pure vector beam polarizations of pz = ±0.55 and deuteron pure tensor beam polarizations of pzz = +0.90 and pzz = −1.50 as well as proton beam polarizations of pz = ±0.75. In this report, we describe both an earlier system and this new improved version, with emphasis on the problems we experienced and the solutions devised to solve them.