Author: Thiry, J.-P.
Paper Title Page
WEPOR011 Lattice Matching with Elegant at ELSA 2690
 
  • J.-P. Thiry, W. Hillert
    ELSA, Bonn, Germany
 
  The electron stretcher ring ELSA provides a beam of polarized electrons of up to 3.2 GeV energy. To preserve the initial degree of polarization, several depolarizing resonances have to be compensated during the fast energy ramp of 6 GeV/s. Beam depolarization, caused by crossing these resonances is studied using comprehensive numerical calculations. These depend essentially on a precise model of the actual magnetic field distributions, explicitly taking into account misalignments. Hence it is necessary to match the theoretical lattice to the actual accelerator. In a first step the alignment of all magnets has been examined and improved. This was done by using standard survey equipment and precise electronic spirit levels. In a second step the concept of response matrix fitting is used for further, beam based, lattice matching. Particle tracking and optics calculations are carried out using elegant, a fully 6D accelerator toolbox. Lattice matching is done by repeatedly calling elegant and utilizing a modified Levenberg-Marquardt optimizer. In this contribution we will describe our lattice fitting implementation.  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPOR011  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)