JACoW is a publisher in Geneva, Switzerland that publishes the proceedings of accelerator conferences held around the world by an international collaboration of editors.
TY - CONF AU - Giacomel, L. AU - Baudrenghien, P. AU - Buffat, X. AU - Calaga, R. AU - Mounet, N. ED - Cai, Yunhai ED - Nagaitsev, Sergei ED - Kim, Dong Eon ED - Marx, Michaela ED - Schaa, Volker R. W. TI - Mitigation Strategies for the Instabilities Induced by the Fundamental Mode of the HL-LHC Crab Cavities J2 - Proc. of HB2023, Geneva, Switzerland, 09-13 October 2023 CY - Geneva, Switzerland T2 - ICFA Advanced Beam Dynamics Workshop on High-Intensity and High-Brightness Hadron Beams T3 - 68 LA - english AB - The transverse impedance is one of the potentially limiting effects for the performance of the High-Luminosity Large Hadron Collider (HL-LHC). In the current LHC, the impedance is dominated by the resistive-wall contribution of the collimators at typical bunch-spectrum frequencies, and is of broad-band nature. Nevertheless, the fundamental mode of the crab cavities, that are a vital part of the HL-LHC baseline, adds a strong and narrow-band contribution. The resulting coupled-bunch instability, which contains a strong head-tail component, requires dedicated mitigation measures, since the efficiency of the transverse damper is limited against such instabilities, and Landau damping from octupoles would not be sufficient. The efficiency and implications of various mitigation strategies, based on RF feedbacks and optics changes, are discussed, along with first measurements using crab cavity prototypes at the Super Proton Synchrotron (SPS). PB - JACoW Publishing CP - Geneva, Switzerland SP - 571 EP - 574 KW - cavity KW - impedance KW - feedback KW - betatron KW - optics DA - 2024/04 PY - 2024 SN - 2673-5571 SN - 978-3-95450-253-0 DO - doi:10.18429/JACoW-HB2023-THBP40 UR - https://jacow.org/hb2023/papers/thbp40.pdf ER -