Author_Institution :
AT-DO, MS H811 Los Alamos National Laboratory, Los Alamos, NM 87545
Abstract :
The high-current levels of contemporary and proposed accelerator facilities induce radiation levels into components, requiring consideration be given to maintenance techniques that reduce personnel exposure. Typical components involved include beamstops, targets, collimators, windows, and instrumentation that intercepts the direct beam. Also included are beam extraction, injection, splitting, and kicking regions, as well as purposeful spill areas where beam tails are trimmed and neutral particles are deposited. Scattered beam and secondary particles activate components all along a beamline such as vacuum pipes, magnets, and shielding. Maintenance techniques vary from "hands-on" to TV-viewed operation using state-of-the-art servomanipulators. Bottom- or side-entry casks are used with thimble-type target and diagnostic assemblies. Long-handled tools are operated from behind shadow shields. Swinging shield doors, unstacking block, and horizontally rolling shield roofs are all used to provide access. Common to all techniques is the need to make operations simple and to provide a means of seeing and reaching the area.