A magnet model for a hybrid undulator assembly

Matti Ryynänen (Corresponding Author)

Research output: Contribution to journalArticleScientificpeer-review

1 Citation (Scopus)

Abstract

A modelling method, in which a single magnet block is divided into several sub-blocks, is described. It is assumed that each sub-block is polarized homogeneously.
The sub-block polarizations are derived with a genetic algorithm, which analytically calculates the total magnet flux density values generated by all sub-blocks and fits it to the values measured at the corresponding points in the vicinity of the magnet. The sub-block modellings accomplished show notable improvement in predicting the magnet flux density within the undulator gap when compared with a model based on homogeneously polarized blocks.
The sub-block model can also be used when discarding bad magnets from a set. Finally, the results show that the inhomogeneities in individual magnets are one of the major reasons for poor predictability of the undulator field in hybrid devices.
Original languageEnglish
Pages (from-to)468-470
JournalJournal of Synchrotron Radiation
Volume5
Issue number3
DOIs
Publication statusPublished - 1998
MoE publication typeA1 Journal article-refereed

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Wigglers
Magnets
magnets
assembly
flux density
Fluxes
genetic algorithms
inhomogeneity
Genetic algorithms
Polarization
polarization

Cite this

Ryynänen, Matti. / A magnet model for a hybrid undulator assembly. In: Journal of Synchrotron Radiation. 1998 ; Vol. 5, No. 3. pp. 468-470.
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A magnet model for a hybrid undulator assembly. / Ryynänen, Matti (Corresponding Author).

In: Journal of Synchrotron Radiation, Vol. 5, No. 3, 1998, p. 468-470.

Research output: Contribution to journalArticleScientificpeer-review

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