Open AccessAnalyses of the factors for the demagnetization of permanent magnets caused by high‐energy electron irradiation
Author(s) -
Asano Yoshihiro,
Bizen Teruhiko,
Maréchal Xavier
Publication year - 2009
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s0909049509008899
Subject(s) - bremsstrahlung , demagnetizing field , irradiation , tantalum , electron , synchrotron , physics , magnet , nuclear physics , monte carlo method , synchrotron radiation , photon , materials science , atomic physics , magnetic field , optics , metallurgy , statistics , magnetization , mathematics , quantum mechanics
Demagnetization owing to high‐energy electron irradiation has been analyzed for permanent magnets used in insertion devices of synchrotron radiation sources, using the Monte Carlo code FLUKA . The experimental data of a thermally treated Nd 2 Fe 14 B permanent magnet with a copper or a tantalum block at electron energies ranging from 2 to 8 GeV were compared with the calculation data of the absorbed doses, photoneutron production distributions and star densities. The results indicate that low‐energy photoneutrons and bremsstrahlung photons are not involved in the demagnetization process, and suggest that the star density owing to the photoneutrons is strongly correlated with the demagnetization process.