Author: Löfgren, P.
Paper Title Page
WEPS030 Ion Optics Alignment in the Electrostatic Double Storage Ring DESIREE 2547
 
  • P. Löfgren, M. Blom, F. Hellberg, L. Liljeby, A. Simonsson
    MSL, Stockholm, Sweden
  • P. Reinhed
    Stockholm University, Stockholm, Sweden
 
  DESIREE is a cryogenic electrostatic double storage ring under construction at Stockholm University. The two rings have similar circumference, 8.8 m and a common straight section for merged beam experiments. In each ring the ions are guided by two 160° cylindrical deflectors and four 10° deflectors and focused by four quadrupole doublets. In terms of ion optics alignment the quadrupoles are the most important factor for the ion beam acceptance and the goal is to align all quadrupoles with precision of 0.1 mm. DESIREE is constructed as a double walled cryostat with an inner and an outer vacuum chamber. All optical elements are mounted directly on the bottom of the inner chamber. For positioning of the ion optics, the bottom plate is prepared with a number of footprints where each footprint consists of four small machined surfaces that define the height and two alignment holes that define the lateral position. The optical elements were aligned on the bottom plate using a portable measuring device in combination with a level instrument. In this work we describe the alignment procedure in detail and report on the overall precision obtained and the consequence for the ion beam.  
 
THPS047 New Injection and Extraction at CRYRING for FLAIR 3529
 
  • A. Simonsson, L. Brännholm, S. Das, A. Källberg, P. Löfgren, A. Paal, J. Sjöholm
    MSL, Stockholm, Sweden
  • H. Danared
    ESS, Lund, Sweden
  • D. Reistad
    Intégro Utbildnings AB, Sigtuna, Sweden
 
  As a preparation for a future transfer of CRYRING to FLAIR at FAIR in Darmstadt, Germany, we have installed and tested a slow extraction system. At FLAIR CRYRING will be used for deceleration of antiprotons from 30 MeV to 0.3 MeV. The tests of the slow extraction show that the beam can be extracted during 2 s with 30-60% efficiency and with rather constant amplitude, apart from noise from 50 Hz harmonics. A new injection system has also been designed. It will be able to inject 30 MeV antiprotons from NESR as well as 0.3 MeV/u ions created in a separate ion source and accelerated in an RFQ.