Experimental studies of multipass beam breakup and energy recovery using the CEBAF injector linac

Beam breakup (BBU) instabilities in superconducting linacs are a significant issue due to the potentially high Q of the cavity higher-order modes (HOMs). The CEBAF accelerator, which employs five pass recirculation through two superconducting linacs to accelerate high CW current (up to 200 μA), poses unique instability problems. An experimental investigation of multipass BBU at CEBAF has been completed using a single recirculation through the CEBAF injector linac. This recirculator is calculated to be more sensitive to the instability than the full CEBAF accelerator. Successful recirculation through the injector of a beam with greater than 200 μA average current from an injection energy of 5.6 MeV to a final energy of 80.1 MeV indicates that BBU should not be a problem in the full CEBAF accelerator. In addition, we were able recover all the energy from a 30 μA 42.8 MeV first pass beam by recirculating it out of phase and decelerating it to a final energy equal to the injection energy (5.6 MeV).

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Physics

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2011

Author dc:creator

• Sereno, Nicholas S.R.

Contributors dc:contributor

• Cardman, Lawrence S.

• Physics, General

Statement dc:rights

• Copyright 1994 Sereno, Nicholas S. R.

Language dc:language

eng

Identifier

AAI9416432
(UMI)AAI9416432

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/19305