Application of Genetic Algorithms to Sorting, Swapping and Shimming of the SOLEIL Undulator Magnets

Journal Article · Fri Jan 19 00:00:00 EST 2007 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.2436074· OSTI ID:21052526

Chubar, O; Rudenko, O; Benabderrahmane, C; Marcouille, O; Filhol, J M; Couprie, M E ^[1]

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1. Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin - BP 48, 91192 GIF-sur-YVETTE CEDEX (France)

Undulators are typically composed of a large number of individual magnets, from tens to many hundreds, depending on undulator type and technology. Characteristics of real magnets often deviate from ideal values, resulting in degradation of the undulator performance. It is known that the imperfections of individual magnets can be mutually compensated, to certain extent, by appropriate sorting of the magnets and/or magnet modules, based on measurements of their individual characteristics, performed before the insertion device (ID) assembly. After the assembly, the quality of the ID magnetic field can be improved by magnet swapping and by shimming, consisting either in small displacements of some of the magnets or in adding small pieces of permanent magnet or soft iron material to appropriate locations of the structure. Mathematically, the magnet sorting, swapping and shimming can be considered as multi-objective constrained optimization problems with large numbers of variables. We show that each of these problems can be efficiently solved by means of Genetic Algorithms with 3D magnetostatics methods and magnetic measurements data used for the fitness calculation. First practical results obtained with three different undulators of the SOLEIL Synchrotron are presented.

• OSTI ID: 21052526
• Journal Information: AIP Conference Proceedings, Vol. 879, Issue 1; Conference: 9. international conference on synchrotron radiation instrumentation, Daegu (Korea, Republic of), 28 May - 2 Jun 2006; Other Information: DOI: 10.1063/1.2436074; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
43 PARTICLE ACCELERATORS
ALGORITHMS
COMPUTER CALCULATIONS
MAGNETIC FIELDS
OPTIMIZATION
PERFORMANCE
PERMANENT MAGNETS
SYNCHROTRON RADIATION
WIGGLER MAGNETS