The final mechanical design, fabrication, and commissioning of a wire scanner and scraper assembly for halo-formation measurements in a proton beam

摘要

The 6.7 MeV, 100 mA proton beam being produced in the Low Energy Demonstration Accelerator (LEDA) RFQ is being injected into a 52 magnet lattice in order to study the charged-beam phenomenon known as beam halo [1]. Quadrupole magnets in the lattice are purposely mismatched to cause or amplify halo formation in the beam. Interceptive diagnostics that consist of a thin wire and a paddle type device called a scraper are placed in the beam to obtain charge-distribution data. The charge-distribution data is used to create a current-density distribution plot of the beam at the probed location [2]. This paper describes the mechanical design, fabrication, and commissioning of the interceptive diagnostic devices and the assembly that carries them.