U.S. Particle Accelerator School

High Brightness, Ultra-Fast Electron Sources course

Sponsoring University:

Boston University

Course:

High Brightness, Ultra-Fast Electron Sources

Instructors:

James Rosenzweig, UCLA and Massimo Ferrario, INFN-Frascati


Purpose and Audience
The creation of intense low emittance - high brightness - electron beams is a key enabling technology that makes possible many of today's most compelling, cutting-edge beam applications, such as x-ray free-electron lasers, Compton scattering sources, and ultra-high gradient wakefield accelerators. This course is especially designed for graduate students and practitioners interested in the development of electron sources.

Prerequisites
Undergraduate mechanics and electricity / magnetism.

Objectives
The devices that are used to create these beams, rf photoinjectors and related pulse compressors have intricate physical
and technical aspects. These characteristics range from ultra-high field radio-frequency accelerating cavities and picosecond lasers on the technical side, to the qualitative change of the beam physics to complete domination of collective field over thermal effects. In this course we will introduce the analytical methods needed to understand the relevant physical effects, notably, as longitudinal dynamics in violently accelerating systems, single component plasma-like transverse beam behavior, and the dynamics of bunching systems. The student would be expected to understand the basic physics, be able to design an electron source and use the computer programs available in such developments.

Instructional Method
This course includes a series of 10 lectures during morning sessions, followed by afternoon discussion and computer sessions.

Course Content
In this course we will introduce the analytical methods needed to understand the relevant physical effects, notably, as longitudinal dynamics in violently accelerating systems, single component plasma-like transverse beam behavior, and the dynamics of bunching systems. As proper control over these physical effects requires correct implementation of the technical systems, we will then discuss the design of rf cavity, laser and magnetic components of electron sources. The practical use of computer codes that illustrate standard device design and beam dynamics simulation problems will be reviewed. Advanced problems from the field, such as asymmetric emittance beams for linear colliders, magnetic and velocity bunching, and high brightness CW superconducting rf photoinjectors will be employed to illuminate the interplay of physics and technology in modern electron sources.

Reading Requirements
(to be provided by the USPAS) "Fundamentals of Beam Physics" by James Rosenzweig, Oxford University Press 2003. A monograph on electron sources being developed by James Rosenzweig and Dave Dowell will also be provided.

Credit Requirements
Students will be evaluated based on performance: homework assignments (60% of final grade) computer lab assignments (40% of final grade).