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 - Richtmann, L.C. AU - Bortot, L. AU - Ravaioli, E. AU - Wiesner, C. AU - Wollmann, D. ED - Zimmermann, Frank ED - Tanaka, Hitoshi ED - Sudmuang, Porntip ED - Klysubun, Prapong ED - Sunwong, Prapaiwan ED - Chanwattana, Thakonwat ED - Petit-Jean-Genaz, Christine ED - Schaa, Volker R.W. TI - Beam-Based Reconstruction of the Shielded Quench-Heater Fields for the LHC Main Dipoles J2 - Proc. of IPAC2022, Bangkok, Thailand, 12-17 June 2022 CY - Bangkok, Thailand T2 - International Particle Accelerator Conference T3 - 13 LA - english AB - Small orbit oscillations of the circulating particle beams have been observed immediately following quenches in the LHC’s superconducting main dipole magnets. Magnetic fields generated during the discharge into the quench heaters were identified as the cause. Since the resulting, shielded field inside the beam screen cannot be measured in-situ, the time evolution of the field has to be reconstructed from the measured beam excursions. In this paper, the field-reconstruction method using rotation in normalized phase space and the optimized fitting algorithm are described. The resulting rise times and magnetic field levels are presented for quench events that occurred during regular operation as well as for dedicated beam experiments. Finally, different approaches to model the shielding behavior of the beam screen are discussed. PB - JACoW Publishing CP - Geneva, Switzerland SP - 1874 EP - 1877 KW - dipole KW - shielding KW - operation KW - optics KW - injection DA - 2022/07 PY - 2022 SN - 2673-5490 SN - 978-3-95450-227-1 DO - doi:10.18429/JACoW-IPAC2022-WEPOPT016 UR - https://jacow.org/ipac2022/papers/wepopt016.pdf ER -