U.S. Particle Accelerator School
High Brightness Electron Injectors and Applications
Sponsors:
University of California, San Diego Extension
Course Name:
High Brightness Electron Injectors and Applications
Instructors:
Daniele Filippetto and Chad Mitchell, Lawrence Berkeley National Lab; Pietro Musumeci, UCLA
Purpose and Audience
Bright electron pulses form the basis for the next generation of ultrafast electron instrumentation, from Free Electron Lasers to time-resolved electron scattering beamlines. This course will guide the students through the main steps of generation, acceleration and manipulation of high phase-space density electron beams, describing both the opportunities and also the present challenges and limitations.
This course is organized to cover the relevant aspects of an electron injector, starting from the definition of figures of merit and requirements, through the physics and dynamics of high brightness beams, both with and without space charge effects. Technologies and measurement techniques in use will be discussed, together with examples of applications. The course is suitable for entry-level graduate students in physics and engineering or for accelerator scientists and engineers interested in the field of electron injectors.
Prerequisites
Undergraduate Electromagnetism, Special Relativity, Classical Mechanics and Electrodynamics at the junior level or higher is required. Some familiarity with Accelerator Physics at the level of USPAS Fundamentals of Accelerator Physics and Technology with Simulations and Measurements Lab or USPAS graduate Accelerator Physics is recommended. Also, attendance of the Photocathode Physics course is the 1st week of the USPAS session, is strongly suggested.
It is the responsibility of the student to ensure that they meet the course prerequisites or have equivalent experience.
Objectives
This course is intended to give the student a broad overview of electron sources and injectors for ultrafast scientific applications, covering the most relevant physics considerations and technological trade-offs in the design, while also providing glimpses of active research areas in the field. Numerical methods and simulation tools for prediction of electron beam evolution along the beamline will be presented. Various applications of high brightness beams will be discussed as examples. The course material will provide the basic tools for the design of practical electron sources and will convey and understanding the essential physics of high brightness electron beams.
Instructional Method
The course will offer a series of lectures during morning sessions, followed by afternoon simulation sessions. During the simulation sessions, the students will be organized in small groups. Group exercises will be introduced to computer simulation codes and techniques, and will be gradually guided to design an electron injector. Each student group will be required to keep a ‘logbook’ during the simulation lab to document work done. Homework problems will be assigned each day and instructors will be available to help answer questions about the homework and lectures during evening exercise sessions. There will be a final exam on the last day of class.
Course Content
The course topics include:
- Requirements for electron sources: concepts of transverse and longitudinal phase space, emittance, brightness. Overview of emission sources and electron photo-guns. Discussion of theoretical and practical limitations. Discussion of different technologies.
- Example applications: ultrafast electron diffraction and Free electron lasers.
- Explanation of numerical methods employed and use of simulation tools, popular simulation codes, multi-objective optimization.
Reading Requirements
Electronic references will be provided during the course that will serve as the primary reference. Also (to be provided by the USPAS) The Theory and Design of Charged Particle Beams, Second Edition, Updated and Expanded by Martin Reiser, Wiley & Sons 2008.
Perspective students can prepare for the course in advance and/or evaluate the fit of the course to their goals by reviewing the materials in a previous version of the course given in the winter 2016 USPAS session /programs/2016/austin/courses/electron-injectors.shtml. The present course may differ significantly.
Students will be evaluated based on performance:homework assignments (50% of final grade), simulation laboratory logbook (25% of final grade), final exam (25% of final grade).
UC San Diego course number: PHYS 40006
Indiana University course number and title on transcript: Physics 671, Advanced Topics in Accelerator Physics
Michigan State University course number: PHY 963
MIT course number: 8.790 Accelerator Physics