U.S. Particle Accelerator School

Fundamentals of Timing and Synchronization with Applications to Accelerators

Sponsoring University:

University of California, Davis

Course Name:

Fundamentals of Timing and Synchronization with Applications to Accelerators
This class is full. Please contact uspas@fnal.gov to have your name added to the waiting list.


Russell Wilcox and Gang Huang, Lawrence Berkeley National Lab

Purpose and Audience
This course is intended for accelerator physicists, operators and electrical engineers who are interested in the design of timing systems and synchronization techniques for particle accelerators and light sources. The course will focus on transmission, measurement and control of high speed electromagnetic signals in transmission lines or waveguides, whether RF/microwave or optical. These systems are important in the distribution of timing reference information in accelerating systems, and diagnostic techniques to measure beams with respect to RF or ultrafast pulse signals. Examples include ultrafast pump/probe experiments in accelerator-based light sources, or diagnostics for short particle bunches. The course should be accessible to those with undergraduate exposure to electromagnetics, optics and electronics.

Lower division undergraduate courses in mathematics including linear algebra, differential equations, and calculus. Undergraduate physics, including electricity and magnetism, waves including physical optics. Working knowledge of basic DC and AC circuit theory. Some exposure or experience with basic signal processing concepts and RF techniques ( mixers, heterodyning, filters) is helpful.

It is the responsibility of the student to ensure that he or she meets the course prerequisites or has equivalent experience.

This course will consist of two parts: an introduction to measurement and control of EM wave propagation methods and technology, followed by examples of timing and synchronization systems and beam timing diagnostic systems for accelerator purposes. Students will learn concepts and techniques that apply equally to EM waves in the RF, microwave and optical domains, as well as differences in their technical implementation. The course will enable students to understand how precise timing signals are transmitted and used in state-of-the-art practical systems. Emphasis will be placed on sub-picosecond, and even sub-femtosecond synchronization of ultrafast pulse optical sources, RF, and particle beams.

Instructional Method
The course will center on laboratory experiments involving RF and optical signal transmission media, RF and optical sources, and methods of detection and control, both analog and digital. The lectures will cover the principles and devices to be used in the laboratory exercises, while homework will consist of analysis and reporting of the experimental data. Students will work with CW and pulsed lasers, RF and optical interferometers, fiber optics, high speed digitizers, FPGA-based signal processors, optical and RF modulators, and other measurement equipment, to test components of high frequency signal transmission and stabilization systems. During daily cycles of lecture/lab/homework we will build up knowledge of the physics and technology of synchronization systems, culminating in construction of a simple, stabilized clock transmission system and measurement thereof. Emphasis is on practical knowledge and application.

Course Content
Fundamental concepts relating to time in EM wave propagation will be developed, including group and phase velocity, polarization, and time and frequency domain descriptions. Processing and control techniques such as phase and amplitude modulation, heterodyning and amplification will be presented, with attention to measurement uncertainty and noise leading to timing uncertainty. The course assumes some familiarity with circuit fundamentals, and will cover RF, optical waves and waveguides, photodetection, interferometers, laser fundamentals, optical coherence, and key RF and fiber optic components (e.g. directional couplers, modulators, harmonic generation, polarization controllers, mixers, amplifiers, and filters). Phase-locked loop control circuits will be discussed, including hybrid microwave/optical loops. The course will stress the complementary time-domain and frequency-domain descriptions of these circuit elements and behavior. Methods of low-noise digital RF detection and control will be covered, centering on FPGA-based, high speed control. Techniques of computation particular to FPGAs will be covered.

The second portion of this class will examine the system implementations of timing distribution in accelerators and light sources. These will include RF phase distribution to accelerator cavities, synchronization of pulsed lasers for photoinjectors and pump/probe experiments, and time references for beam diagnostics. Techniques to measure beam timing will be discussed. Related applications will be discussed to illustrate other uses of these techniques.

Reading Requirements
A collection of papers from the optical, microwave and accelerator literature will be provided. Other suggested references are "Lightwave Technology: Telecommunication Systems" by Govind P. Agrawal, Wiley-Interscience (2005) and "Fields and Waves in Communication Electronics" Third Edition, by Simon Ramo, John R. Whinnery and Theodore Van Duzer, Wiley Publishers (1994)

Credit Requirements
Students will be evaluated on performance as follows: lab sessions (50%), homework (50%).

UC Davis course number:
163EDN671 Advanced Topics
Indiana University course number: Physics 671, Advanced Topics in Accelerator Physics
Michigan State University course number: PHY 963, U.S. Particle Accelerator School
MIT course number: 8.790, Accelerator Physics