Author: Volz, P.I.
Paper Title Page
THPOPT052 The Status of the In-Vacuum-APPLE II Undulator IVUE32 at HZB / BESSY II 2716
 
  • J. Bahrdt, J. Bakos, S. Gaebel, S. Gottschlich, S. Grimmer, S. Knaack, C. Kuhn, F. Laube, A. Meseck, C. Rethfeldt, E.C.M. Rial, A. Rogosch-Opolka, M. Scheer, P.I. Volz
    HZB, Berlin, Germany
 
  At BESSY II, two new beamlines for RIXS and for X-Ray-microscopy demand a short period variably polarizing undulator. For this purpose, the first in-vacuum APPLE undulator worldwide is under construction. The parameters are as follows: period length=32mm, magnetic length=2500mm, minimum gap=7mm. The design incorporates a force compensation scheme as proposed by two of the authors at the SRI2018. All precision parts of the drive chain are located in air. New transverse slides for the transversal slit adjustment have been developed and tested. Optical micrometers measure the gap and shift positions, similar to the system of the CPMU17 at BESSY II. They provide the signals for motor feedback loops. A new UHV-compatible soldering technique, as developed with industry, relaxes fabrication tolerances of magnets and magnet holders and simplifies the magnet assembly. A 10-period prototype has been setup for lifetime tests of the new magnetic keeper design. The paper describes first results of the prototype and other key-components and summarizes the status of the full-scale undulator.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT052  
About • Received ※ 19 May 2022 — Revised ※ 10 June 2022 — Accepted ※ 11 June 2022 — Issue date ※ 22 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPOPT053 Goubau-Line Set Up for Bench Testing Impedance of IVU32 Components 2719
SUSPMF023   use link to see paper's listing under its alternate paper code  
 
  • P.I. Volz, A. Meseck
    HZB, Berlin, Germany
  • A. Meseck
    KPH, Mainz, Germany
 
  The worldwide first in-vacuum elliptical undulator, IVUE32, is being developed at Helmholtz-Zentrum Berlin. The 2.5 m long device with a period length of 3.2 cm and a minimum gap of about 7 mm is to be installed in the BESSY II storage ring. It will deliver radiation in the soft X-ray range to several beamlines. The proximity of the undulator structure to the electron beam makes the device susceptible to wakefield effects which can influence beam stability. A complete understanding of its impedance characteristics is required prior to installation and operation, as unforeseen heating of components could have catastrophic consequences. To understand and measure the IVU’s impedance characteristics a Goubau-Line test stand is being designed. A Goubau-line is a single wire transmission line for high frequency surface waves with a transverse electric field resembling that of a charged particle beam out to a certain radial distance. A concept optimized for bench testing IVUE32-components will be discussed, microwave simulations will be presented together with first measurements from a test stand prototype.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT053  
About • Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 16 June 2022
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)