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Title: Monte Carlo Study in Radiation Damage Experiments of Permanent Magnets by High Energy Electrons

Abstract

The demagnetization of permanent magnets used in the insertion device, becomes one of the most important issues of the next generation light sources. The demagnetization experiment has been carried out at the electron linac of Pohang Light Source. To find out the mechanism of radiation damage to the magnet, the radiation field around and inside the target and magnet in the experiment is investigated with Monte Carlo code FLUKA (2005 version). The energy spectra of photons and neutrons around the target and magnet are derived and analyzed The 3-dimensional dose distributions in the target and magnet due to 2 GeV incident electrons and secondary particles are also calculated. The calculated results under different target conditions (Cu, Ta target or no target) are compared. Some important parameters such as dose and 1 MeV equivalent fluence are summarized. Finally the demagnetization of the magnet due to radiation at high energy accelerator is discussed.

Authors:
 [1];  [2]; ;  [1];  [3]
  1. Pohang Accelerator Laboratory, POSTECH, Nam-gu, Pohang, 790-784 (Korea, Republic of)
  2. (China)
  3. Department of Engineering Physics, Tsinghua University, Beijing, 100084 (China)
Publication Date:
OSTI Identifier:
21052544
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 879; Journal Issue: 1; Conference: 9. international conference on synchrotron radiation instrumentation, Daegu (Korea, Republic of), 28 May - 2 Jun 2006; Other Information: DOI: 10.1063/1.2436090; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY; DEMAGNETIZATION; ELECTRON BEAMS; ELECTRONS; ENERGY SPECTRA; GEV RANGE; LINEAR ACCELERATORS; MEV RANGE; MONTE CARLO METHOD; NEUTRONS; PERMANENT MAGNETS; PHOTONS; POHANG LIGHT SOURCE; RADIATION DOSE DISTRIBUTIONS; RADIATION EFFECTS; THREE-DIMENSIONAL CALCULATIONS

Citation Formats

Qiu Rui, Department of Engineering Physics, Tsinghua University, Beijing, 100084, Lee, Hee-Seock, Koo, Tae-Yeong, and Li Junli. Monte Carlo Study in Radiation Damage Experiments of Permanent Magnets by High Energy Electrons. United States: N. p., 2007. Web. doi:10.1063/1.2436090.
Qiu Rui, Department of Engineering Physics, Tsinghua University, Beijing, 100084, Lee, Hee-Seock, Koo, Tae-Yeong, & Li Junli. Monte Carlo Study in Radiation Damage Experiments of Permanent Magnets by High Energy Electrons. United States. doi:10.1063/1.2436090.
Qiu Rui, Department of Engineering Physics, Tsinghua University, Beijing, 100084, Lee, Hee-Seock, Koo, Tae-Yeong, and Li Junli. Fri . "Monte Carlo Study in Radiation Damage Experiments of Permanent Magnets by High Energy Electrons". United States. doi:10.1063/1.2436090.
@article{osti_21052544,
title = {Monte Carlo Study in Radiation Damage Experiments of Permanent Magnets by High Energy Electrons},
author = {Qiu Rui and Department of Engineering Physics, Tsinghua University, Beijing, 100084 and Lee, Hee-Seock and Koo, Tae-Yeong and Li Junli},
abstractNote = {The demagnetization of permanent magnets used in the insertion device, becomes one of the most important issues of the next generation light sources. The demagnetization experiment has been carried out at the electron linac of Pohang Light Source. To find out the mechanism of radiation damage to the magnet, the radiation field around and inside the target and magnet in the experiment is investigated with Monte Carlo code FLUKA (2005 version). The energy spectra of photons and neutrons around the target and magnet are derived and analyzed The 3-dimensional dose distributions in the target and magnet due to 2 GeV incident electrons and secondary particles are also calculated. The calculated results under different target conditions (Cu, Ta target or no target) are compared. Some important parameters such as dose and 1 MeV equivalent fluence are summarized. Finally the demagnetization of the magnet due to radiation at high energy accelerator is discussed.},
doi = {10.1063/1.2436090},
journal = {AIP Conference Proceedings},
number = 1,
volume = 879,
place = {United States},
year = {Fri Jan 19 00:00:00 EST 2007},
month = {Fri Jan 19 00:00:00 EST 2007}
}
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