LAMPF Transition-Region Mechanical Fabrication

The new Transition Region (TR-II) optimizes phase matching of H+ and H- beams during simultaneous transport between the drift-tube linac and side-coupled linac at LAMPF. Improvements include larger aperture, a straight beam track, greater beam path length adjustments, and better utility routing. Hardware density required innovative designs for magnets, mounting, vacuum, and utilities. Dipoles are powered by one constant current and one variable current supply which cause the fields to add or buck providing ± 20-mm path length variation for phase matching. Alignment was done using two digital theodolites coupled to a computer to give real-time three-dimensional data. Production beams up to 950 ?A at 100 MeV have been routinely transported since September 1983.