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URLhttps://doi.org/10.18429/JACoW-IPAC2025-MOCN3
TitleSearches for RF breakdown precursors using Cherenkov light in optical fibers
Authors
  • P. Pushkarna, G. Taylor, J. Valerian, M. Volpi, P. Giansiracusa, R. Rassool
    The University of Melbourne
  • R. Dowd, S. Sheehy, Y. Tan
    Australian Nuclear Science and Technology Organisation
AbstractRF breakdown studies are crucial for machines relying on high-gradient, normal-conducting RF accelerating cavities. Searches for breakdown precursors in high-gradient test-stand data have been conducted* and highlight the need for a new diagnostic with improved temporal response**. Emission of Cherenkov light in optical fibers has been identified as one such diagnostic***, which occurs when charge showers due to breakdown are incident on the fiber. Optical fibers have been used previously as distributed Beam Loss Monitors. At the X-Band Laboratory for Accelerators and Beams (X-LAB), we position optical fibers adjacent to X-band cavities being conditioned for the proposed Compact Linear Collider (CLIC). We assess sensitivity of fibers to charge emitted by field emission and breakdown events. Since breakdown precursors may occur at sub-microsecond timescales**, we survey photon detectors best suited to examining fiber response and identifying precursors. We compare fiber signals to dark current captured by upstream and downstream Faraday Cups. In search of precursory phenomena, pulse-by-pulse evolution of fiber signals is examined for field-emission activity prior to breakdown.
Paperdownload: MOCN3.pdf
CiteBibTeX, LaTeX, Text/Word, RIS, EndNote
Conference16th International Particle Accelerator Conference
Series
LocationTaipei, Taiwan
Date01-06 Jun 2025
PublisherJACoW Publishing, Geneva, Switzerland
Editorial Board* Ming-Chyuan Lin - National Synchrotron Radiation Research Center * Yoichi Sato - KEK * Jui-Che Huang - National Synchrotron Radiation Research Center * David Button - Australian Nuclear Science and Technology Organisation * Ping-Shun Chuang - National Synchrotron Radiation Research Center
Online ISBN978-3-95450-248-6
Online ISSN2673-5490
Received28 May 2025
Revised02 June 2025
Accepted03 June 2025
Issued05 November 2025
DOI10.18429/JACoW-IPAC2025-MOCN3
Pages65-68