A polarized hydrogen/deuterium atomic beam source for internal target experiments

A high-brightness hydrogen/deuterium atomic beam source is presented. The a pparatus, previously used in electron scattering experiments with tenser-po larized deuterium (Ferro-Luzzi et al., Phys. Rev. Lett. 77 (1996) 2630; van den Brand et al., Phys. Rev. Lett. 78 (1997) 1235; Zhou et al., Phys. Rev. Lett. 82 (1998) 687; Bouwhuis et al., Phys. Rev. Lett. 82 (1999) 3755), wa s configured as a source for internal target experiments to measure single- and double-polarization observables, with either polarized hydrogen or vec tor/tensor polarized deuterium. The atomic beam intensity was enhanced by a factor of similar to 2.5 by optimizing the Stern-Gerlach focusing system u sing high tip-field ( similar to 1.5 T) rare-earth permanent magnets, and b y increasing the pumping speed in the beam-formation chamber. Fluxes of (5. 9 +/- 0.2) x 10(16) H-1/s were measured in a empty set 12 mm x 122 mm compr ession tube with its entrance at a distance of 27 cm from the last focusing element. The total output flux amounted to (7.6 +/- 0.2) x 10(16) H-1/s. ( C) 2000 Elsevier Science B.V. All rights reserved.