U.S. Particle Accelerator School

Large Scale Metrology of Accelerators course

Sponsoring University:

Cornell University


Large Scale Metrology of Accelerators


Robert Ruland and Catherine LeCocq, SLAC

Purpose and Audience
The purpose of this course is to introduce the students to the mechanical alignment of particle beam accelerators. This course is suitable for last year undergraduate physics students or students from other fields who want to gain a deeper understanding of the methodology applied to Large Scale Metrology (LSM) Accelerator Alignment. This course also can provide a broader background to engineers and technicians working in the particle accelerator field.

Elementary concepts of Probability Theory and Statistics, Linear Algebra.

This introductory course tries to avoid heavy mathematical treatment and will focus on the basic principles of LSM as applied to the alignment of particle accelerators. Fundamental principles of geodesy which are needed to build global and local reference frames are introduced. The geodesy specific notation of least-squares data analysis is presented. Survey and alignment procedures and technologies are explored, with emphasis on applications found in the field of particle accelerators. On completion of this course, the students are expected to understand the basic approach to accelerator alignment. Furthermore, they will be able to analyze the geometry of alignment reference networks and of survey observations using provided code.

Instructional Method
This course includes a series of lectures during morning and afternoon sessions. The afternoon sessions will usually include laboratory sessions, which will introduce students to computer simulations and data analysis, and provide hands-on exploration of alignment equipment. Problem sets may be assigned and will be expected to be completed outside of scheduled class sessions. Two instructors will be available at all times.

Course Content
Introductory material will center on discussions of the fundamental principles of geodesy necessary to understand the geoid and its implication for the high precision alignment of large-scale accelerators. Relationships between various references systems will be studied. Survey and alignment instrumentation including GPS will be introduced and their principles of operation explained. Special emphasis will be given in differentiating the instruments for specific applications and the obtainable measurements accuracy. Examples of recent alignment projects are discussed as well as an outlook given on the design of alignment systems for accelerators under construction.

Reading Requirements
“Magnet Support and Alignment”, R. Ruland, SLAC Pub 6461, 1994, http://www.slac.stanford.edu/cgi-wrap/getdoc/slac-pub-6461.pdf

Further optional reading:
“Geodesy”, W. Torge, 2 nd Edition, de Gryter, Berlin, 1991
“Surveying”, H. Kahmen, W. Faig, de Gryter, New York, 1988
“GPS – Theory and Practice”, B. Hofmann-Wellenhof, et.al., 5 th Edition, Springer Verlag, New York, 2001

Credit Requirements
Students will be evaluated based on performance: final exam (30 % of final grade), homework assignments (50 % of final grade) computer/lab sessions (20 % of final grade).