Author: Longhi, E.C.
Paper Title Page
MOPEA066 Investigation and Test of the Possibility of Reducing the Emittance of the Diamond Storage Ring 234
  • B. Singh, M. Apollonio, R. Bartolini, E.C. Longhi
    Diamond, Oxfordshire, United Kingdom
  • R. Bartolini, T. Pulampong
    JAI, Oxford, United Kingdom
  Theoretical and experimental studies have been carried out at the Diamond Light Source to assess the possibility of reducing the emittance of the existing storage ring by means of a change to the optics. The optics solutions obtained so far using a Multi Objective Genetic Algorithm (MOGA) increase the dispersion and the horizontal beta function in the straight section. While the emittance can be reduced to 2.1 nm this optics is limited by the operation of high field superconducting wiggler devices. In this report we present details of the new optics and present results of practical tests. We also compare the theoretical emittance growth due to a wiggler in a dispersive region with test results.  
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.  
WEPWA006 Beam Heat Load Measurements with COLDDIAG at the Diamond Light Source 2135
  • S. Gerstl, S. Casalbuoni, A.W. Grau, T. Holubek, D. Saez de Jauregui, R. Voutta
    KIT, Eggenstein-Leopoldshafen, Germany
  • R. Bartolini, M.P. Cox, E.C. Longhi, G. Rehm, J.C. Schouten, R.P. Walker
    Diamond, Oxfordshire, United Kingdom
  • M. Migliorati, B. Spataro
    INFN/LNF, Frascati (Roma), Italy
  Understanding the heat load from an electron beam is still an open issue for the cryogenic design of superconducting insertion devices. COLDDIAG, a cold vacuum chamber for diagnostics was designed and built specially for this purpose. With the equipped instrumentation, which covers temperature sensors, pressure gauges, mass spectrometers as well as retarding field analyzers it is possible to measure the beam heat load, total pressure, and gas content as well as the net flux and energy of particles hitting the chamber walls. Following a failure after its first installation in November 2011, COLDDIAG was subsequently reinstalled in the Diamond storage ring in August 2012. We report on the preliminary results that have been obtained since then.  
WEPWA062 Status of the UK Superconducting Planar Undulator Project 2259
  • J.A. Clarke, B.J.A. Shepherd
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  • V. Bayliss, T.W. Bradshaw, S.A. Brown, A.J. Brummitt, G.W. Burton, S.J. Canfer, B. Green, S.R. Watson
    STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
  • S.E. Hughes, E.C. Longhi, J.C. Schouten
    Diamond, Oxfordshire, United Kingdom
  The UK is developing a short period, narrow aperture, planar superconducting undulator that is planned to be installed and tested in the 3 GeV Diamond Light Source in 2014. This paper will describe the main parameters of the undulator and the key design choices that have been made. First measurements will be presented of a 19 period test module and also the commissioning of the 2K cryogenic turret.