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URLhttps://doi.org/10.18429/JACoW-IPAC2025-MOPM031
TitleTapering schemes for FCCee
Authors
  • D. Domange
    European Organization for Nuclear Research, Université Libre de Bruxelles
  • C. Hernalsteens, D. Wollmann, G. Roy, K. André
    European Organization for Nuclear Research
AbstractThe electron-positron Future Circular Collider (FCC-ee) is designed to operate at four beam energies, from 45.6 GeV to 182.5 GeV. At such energy levels, the circulating beam loses a significant fraction of its energy via synchrotron radiation. As a single RF insertion is foreseen in the ring, large closed-orbit shifts featuring a typical sawtooth pattern and optics distortions are induced. This in turn leads to a significant reduction of the dynamic aperture if no mitigation is implemented. The solution is to adapt the fields of the magnets to the local beam energy which is referred to as "tapering". For practical reasons, this field adjustment must be realized for groups of magnets to limit the number of powering circuits. An algorithm has bean established to self-consistently compute the tapering strengths of a given scheme, the RF phase required to compensate the energy loss and the required orbit corrections. Tapering scenarios, from coarse schemes to fine grained options are studied with the XSuite tracking code in terms of closed-orbit excursion and optics distortion. The results at the Z-pole (45.6 GeV) and $t\bar t$ (182.5 GeV) energies are discussed in detail.
Paperdownload: MOPM031.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
Revised05 June 2025
Accepted05 June 2025
Issued05 November 2025
DOI10.18429/JACoW-IPAC2025-MOPM031
Pages370-373