Tracing back measured magnetic field imperfections in LHC magnets by means of the inverse problem approach

Author

Russenschuck, S. ; Tortschanoff, T. ; Ijspeert, A. ; Perin, R. ; Siegel, N.

Author_Institution

CERN, Geneva, Switzerland

Volume

30

Issue

4

fYear

1994

fDate

7/1/1994 12:00:00 AM

Firstpage

1797

Lastpage

1800

Abstract

After measuring the magnetic field of a model or prototype superconducting magnet for the Large Hadron Collider (LHC) an inverse field problem is formulated in order to explain the origin of the content of unwanted multipole terms. The inverse problem solving is done by means of a least-squares minimization using the Levenberg-Marquard algorithm. Although the uniqueness of the results remains uncertain, useful insights into the causes of measured field imperfections can be deduced. A model dipole magnet, a main quadrupole prototype and a combined dipole-sextupole corrector magnet are given as examples

Keywords

inverse problems; least squares approximations; proton accelerators; storage rings; superconducting magnets; synchrotrons; LHC; LHC magnets; Large Hadron Collider; Levenberg-Marquard algorithm; combined dipole-sextupole corrector magnet; dipole magnet; inverse problem approach; least-squares minimization; magnetic field imperfections; quadrupole prototype; superconducting magnet; unwanted multipole terms; Coils; Computer errors; Conductors; Inverse problems; Large Hadron Collider; Magnetic field measurement; Magnets; Minimization methods; Prototypes; Tensile stress;

fLanguage

English

Journal_Title

Magnetics, IEEE Transactions on

Publisher

ieee

ISSN

0018-9464

Type

jour

DOI

10.1109/20.305610

Filename

305610