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 - Oeftiger, A. AU - Singh, R. ED - Forck, Peter ED - Wawrzyniak, Adriana ED - Schaa, Volker R.W. ED - Kowalski, Grzegorz W. ED - Cudek, Agnieszka (SOLARIS, Kraków TI - Diagnostics with Quadrupole Pick-Ups at SIS18 J2 - Proc. of IBIC2022, Kraków, Poland, 11-15 September 2022 CY - Kraków, Poland T2 - International Beam Instrumentation Conference T3 - 11 LA - english AB - The beam quadrupole moment of stored beams can be measured with a four-plate quadrupole pick-up. The frequency spectrum of the quadrupole moment contains not only the usual first-order dipole modes (the betatron tunes) but also the second-order coherent modes, comprising of (1.) (even) normal envelope modes, (2.) odd (skew) envelope modes and (3.) dispersion modes. As a novel diagnostic tool, the measured frequencies and amplitudes provide direct access to transverse space charge strength through the tune shift as well as linear coupling (and mismatch thereof), along with the benefit of a non-invasive beam-based measurement. Technically, quadrupole moment measurements require a pick-up with non-linear position sensitivity function. We discuss recent developments and depict measurements at the GSI SIS18 heavy-ion synchrotron. PB - JACoW Publishing CP - Geneva, Switzerland SP - 186 EP - 191 KW - quadrupole KW - pick-up KW - space-charge KW - simulation KW - synchrotron DA - 2022/12 PY - 2022 SN - 2673-5350 SN - 978-3-95450-241-7 DO - doi:10.18429/JACoW-IBIC2022-TU1I2 UR - https://jacow.org/ibic2022/papers/tu1i2.pdf ER -