Author: Gavaldà, X.
Paper Title Page
MOPEA007 Study of Lower Emittance Optics Using Multi-Bend-Achromat Lattice at SOLEIL 76
 
  • R. Nagaoka, P. Brunelle, X. Gavaldà, M. Klein, A. Loulergue, A. Nadji, L.S. Nadolski, M.-A. Tordeux
    SOLEIL, Gif-sur-Yvette, France
  
  In the frame­work of a fu­ture up­grade of the SOLEIL 354 m long and 2.75 GeV stor­age ring, a se­ries of lat­tice stud­ies has been launched to aim at re­duc­ing by an order of mag­ni­tude the cur­rent 4 nm.​rad hor­i­zon­tal emit­tance. In this ex­er­cise, the main con­straint im­posed is to leave all the ex­ist­ing 24 straight sec­tions for in­ser­tion de­vices un­touched. In the pre­vi­ous study (pre­sented at IPAC 2012), the pos­si­bil­ity of using su­per­bends and ex­ploit­ing their lon­gi­tu­di­nal di­pole field vari­a­tion was pur­sued in low­er­ing the emit­tance, find­ing so­lu­tions with a hor­i­zon­tal emit­tance in the sub nanome­ter range. In the pre­sent study, the use of MBA (Multi-Bend-Achro­mat) lat­tice is ex­plored, which is widely rec­og­nized today as the op­ti­mal lat­tice in reach­ing an ul­tra-low emit­tance. The study aims to clar­ify the adapt­abil­ity of the MBA and the range of at­tain­able emit­tance for the SOLEIL ring, in view par­tic­u­larly of the short straight sec­tions ex­ist­ing in half of the orig­i­nal DBA cells in be­tween the dipoles. The pos­si­bil­ity of com­bin­ing the pre­vi­ously ob­tained su­per­bend so­lu­tions with the MBA lat­tice is also ex­am­ined.  
 
TUPWO042 Modeling Results from Magnetic and Beam Based Measurements of the ALBA Gradient Dipoles 1967
 
  • X. Gavaldà
    SOLEIL, Gif-sur-Yvette, France
  • G. Benedetti, J. Marcos, Z. Martí
    CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
  
  The ALBA lat­tice is a DBA-like struc­ture where most of ver­ti­cal fo­cus­ing is pro­vided by gra­di­ent dipoles. In the first year of ma­chine op­er­a­tion, the model pa­ra­me­ters de­scrib­ing the fo­cus­ing strength of the 32 dipoles have been cal­i­brated by fit­ting the mea­sured closed orbit re­sponse ma­trix. The mean k-value ob­tained from this analy­sis dif­fers by -0.3% with re­spect to the value taken from the mag­netic mea­sure­ments pre­vi­ous to the mag­net in­stal­la­tion, while the k vari­a­tion within the 32 dipoles is of the same order of mag­ni­tude. The op­tics re­sults (tunes, beta beat­ing, dis­per­sion) ob­tained with the beam based model are com­pared with the pre­dicted ones from the mag­netic mea­sure­ment model.