U.S. Particle Accelerator School

Damping Ring Design and Physics Issues course

Sponsoring University:

Texas A&M University


Damping Ring Design and Physics Issues


Andy Wolski, University of Liverpool and the Cockcroft Institute and James Jones, CCLRC-ASTeC and the Cockcroft Institute

Purpose and Audience
The purpose of this course is to introduce students to the design and physics issues of linear collider damping rings. This course is suitable for anyone who has a basic understanding of the physics of electron storage rings, and who also has an interest in the specific challenges presented by damping rings.

Basics of accelerator physics for electron storage rings.

By the end of the course, students should be able to:
- describe the performance requirements of linear collider damping rings;
- explain the issues involved in optimization of values for the circumference, beam energy, and other parameters, and explain how the parameters for the ILC damping rings (for example) have been arrived at;
- explain the physics behind potentially limiting beam dynamics effects, including acceptance, vertical emittance, microwave instability, resistive-wall instability, intrabeam scattering, electron cloud effects and ion effects;
- perform initial assessments of the likely impact of certain potentially limiting effects, stating the relevant assumptions;
- describe the requirements for key technical subsystems, including the injection/extraction kickers, vacuum system, and the damping wigglers.

Instructional Method
There will be four mornings spent on lectures. Afternoon sessions will be used for both additional lectures and reviewing set problems. There will be homework and a final examination.

Course Content
The performance requirements of linear collider damping rings will be explored, and appropriate parameter regimes considered. Beam dynamics problems related to single-particle dynamics (dynamic aperture and acceptance, low-emittance tuning) and collective effects (microwave instability, resistive-wall instability, space-charge tune shifts, intrabeam scattering, electron cloud and ion effects) will be discussed. The requirements for some of the technical subsystems, including the injection/extraction kickers and the damping wigglers, will be considered in the context of present capabilities.

Credit Requirements
Students will be evaluated based on performance: final exam (50 % of final grade), homework assignments (50 % of final grade).