Keyword: resonance
Paper Title Other Keywords Page
MOPB16 Continuous Beam Energy Measurements at Diamond Light Source polarization, beam-losses, operation, wiggler 107
  • N. Vitoratou, P. Karataev
    Royal Holloway, University of London, Surrey, United Kingdom
  • P. Karataev
    JAI, Egham, Surrey, United Kingdom
  • G. Rehm
    DLS, Oxfordshire, United Kingdom
  Resonant Spin Depolarization (RSD) is a well-known technique that has been employed by Diamond Light Source (DLS) for beam energy measurements. In this project, we study a new approach to make RSD compatible with user beam operation and provide a continuously updated online measurement. An array of four custom-made scintillation detectors has been installed around the beam pipe, downstream of collimators to capture the highest fraction of lost particles and maximize the count rate. The excitation is gated to half of the stored bunches and the acquisition system counts losses in both halves independently. Using the count in the un-excited part for normalisation suppresses external factors that modify the loss rate. Different parameters of the measurement, like excitation kick strength and duration have been explored to optimise depolarisation and to increase the reliability of the measurement.  
poster icon Poster MOPB16 [3.136 MB]  
DOI • reference for this paper ※  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
TUPB04 Development of a New Button Beam-position Monitor for BESSY VSR impedance, vacuum, storage-ring, operation 265
  • J.G. Hwang, V. Dürr, M. Ries, A. Schälicke, G. Schiwietz, D. Wolk
    HZB, Berlin, Germany
  An extreme operation mode such as the BESSY-VSR conditions stimulates the development of a high accuracy bunch-by-bunch beam-position monitor (BPM) system which is compatible with the bunch-selective operation for the orbit feedback system. Such a system will also greatly benefit to accelerator R&D such as transverse resonance island buckets (TRIBs). Compensation of the long-range ringing signal produced by the combined effect of impedance mismatching inside the button and trapped TE-modes in the aluminum-oxide insulator (Al2O3) material is required essentially to improve the resolution. This is important since the ringing causes a misreading of the beam position and current of following bunches. We show the design study of a new button-type BPM to mitigate the influence of the ringing signal as well as to reduce wake losses by improving the impedance matching in the button and by replacing the insulator material.  
DOI • reference for this paper ※  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
TUPB05 Design of a Cavity Beam Position Monitor for the ARES Accelerator at DESY dipole, cavity, FEL, simulation 269
  • D. Lipka, M. Dohlus, M. Marx, S. Vilcins, M. Werner
    DESY, Hamburg, Germany
  The SINBAD facility (Short and INnovative Bunches and Accelerators at DESY) is foreseen to host various experiments in the field of production of ultra-short electron bunches and novel high gradient acceleration techniques. The SINBAD linac, also called ARES (Accelerator Research Experiment at SINBAD), will be a conventional S-band linear RF accelerator allowing the production of low charge (within a range between 0.5 pC and 1000 pC) ultra-short electron bunches. To detect the low charge bunches a cavity beam position monitor is designed based on the experience from the EU-XFEL. It will consist of a stainless steel body with low Q factor of 70, a resonance frequency of 3.3 GHz and a relative wide gap of 15 mm to reach a high peak position sensitivity of 4.25 V/(nC mm). The design considerations and simulation results will be presented.  
DOI • reference for this paper ※  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)