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Title: Quadruple-bend achromatic low emittance lattice studies

Abstract

A quadruple-bend achromatic (QBA) cell, defined as a supercell made of two double-bend cells with different outer and inner dipole bend angles, is found to provide a factor of 2 in lowering the beam emittance relative to the more conventional double-bend achromat. The ratio of bending angles of the inner dipoles to that of the outer dipoles is numerically found to be about 1.5-1.6 for an optimal low beam emittance in the isomagnetic condition. The QBA lattice provides an advantage over the double-bend achromat or the double-bend nonachromat in performance by providing a small natural beam emittance and some zero-dispersion straight sections. A lattice with 12 QBA cells and a preliminary dynamic aperture study serves as an example.

Authors:
; ; ; ; ; ; ; ;  [1];  [2]
  1. National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan (China)
  2. (United States)
Publication Date:
OSTI Identifier:
20953459
Resource Type:
Journal Article
Resource Relation:
Journal Name: Review of Scientific Instruments; Journal Volume: 78; Journal Issue: 5; Other Information: DOI: 10.1063/1.2740070; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; APERTURES; BEAM EMITTANCE; BENDING; DIPOLES; DISPERSIONS; PARTICLE BEAMS; PERFORMANCE; STORAGE RINGS; SYNCHROTRON RADIATION

Citation Formats

Wang, M. H., Chang, H. P., Chao, H. C., Chou, P. J., Kuo, C. C., Tsai, H. J., Lee, S. Y., Tam, W. M., Wang, F., and Department of Physics, Indiana University, Bloomington, Indiana 47405. Quadruple-bend achromatic low emittance lattice studies. United States: N. p., 2007. Web. doi:10.1063/1.2740070.
Wang, M. H., Chang, H. P., Chao, H. C., Chou, P. J., Kuo, C. C., Tsai, H. J., Lee, S. Y., Tam, W. M., Wang, F., & Department of Physics, Indiana University, Bloomington, Indiana 47405. Quadruple-bend achromatic low emittance lattice studies. United States. doi:10.1063/1.2740070.
Wang, M. H., Chang, H. P., Chao, H. C., Chou, P. J., Kuo, C. C., Tsai, H. J., Lee, S. Y., Tam, W. M., Wang, F., and Department of Physics, Indiana University, Bloomington, Indiana 47405. Tue . "Quadruple-bend achromatic low emittance lattice studies". United States. doi:10.1063/1.2740070.
@article{osti_20953459,
title = {Quadruple-bend achromatic low emittance lattice studies},
author = {Wang, M. H. and Chang, H. P. and Chao, H. C. and Chou, P. J. and Kuo, C. C. and Tsai, H. J. and Lee, S. Y. and Tam, W. M. and Wang, F. and Department of Physics, Indiana University, Bloomington, Indiana 47405},
abstractNote = {A quadruple-bend achromatic (QBA) cell, defined as a supercell made of two double-bend cells with different outer and inner dipole bend angles, is found to provide a factor of 2 in lowering the beam emittance relative to the more conventional double-bend achromat. The ratio of bending angles of the inner dipoles to that of the outer dipoles is numerically found to be about 1.5-1.6 for an optimal low beam emittance in the isomagnetic condition. The QBA lattice provides an advantage over the double-bend achromat or the double-bend nonachromat in performance by providing a small natural beam emittance and some zero-dispersion straight sections. A lattice with 12 QBA cells and a preliminary dynamic aperture study serves as an example.},
doi = {10.1063/1.2740070},
journal = {Review of Scientific Instruments},
number = 5,
volume = 78,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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