Author: Fielder, R.T.
Paper Title Page
TUPWA052 Loss Factor and Impedance Analysis for the Diamond Storage Ring 1826
 
  • R. Bartolini, R.T. Fielder, C.A. Thomas
    Diamond, Oxfordshire, United Kingdom
 
  Diamond Light Source is investigating the possibility of increasing the storage ring operating current above the nominal 300 mA. A campaign of measurements and simulations has been carried out in order to understand the extent of the parasitic energy loss and characterise the most important items which build up the machine impedance. In this paper we report on the most recent measurements of the longitudinal loss factor and the present status of the impedance database with an initial comparison between the two.  
 
TUPWO057 Active Shimming of Dynamic Multipoles of an APPLE II Undulator in the Diamond Storage Ring 1997
 
  • B. Singh, R. Bartolini, R.T. Fielder, E.C. Longhi, I.P.S. Martin, S.P. Mhaskar, R.P. Walker
    Diamond, Oxfordshire, United Kingdom
  • R. Bartolini
    JAI, Oxford, United Kingdom
 
  Diamond plans to operate a 5 m, long period length, APPLE undulator in a long insertion straight section. Theoretical investigations showed a severe impact on machine dynamics especially when the device is operated in vertical polarization mode. The use of local optics corrections and/or lowering of beta functions were initially investigated as possible solutions but with limited success. Active shimming of dynamic multipoles, following the approach at BESSY-II, proved more effective. The optimum shiming has been devised using kick map approach. In this paper we review the theoretical analysis, the commissioning of the active shims and the undulator, and the net effect of the undulator after compensation.