The Joint Accelerator Conferences Website (JACoW) is an international collaboration that publishes the proceedings of accelerator conferences held around the world.
TY - CONF AU - Wolff-Fabris, F. AU - Li, Y. AU - Pflüger, J. ED - Bishofberger, Kip:Carlsten, Bruce (LANL, Los Alamos, NM, USA)[ORCID:0000-0001-5619-907X] ED - Schaa, Volker RW TI - The Magnetic Field Integral Hysteresis on the European XFEL Gap Movable Undulator Systems J2 - Proc. of FEL2017, Santa Fe, NM, USA, August 20-25, 2017 C1 - Santa Fe, NM, USA T2 - International Free Electron Laser Conference T3 - 38 LA - english AB - The European XFEL GmbH is a new X-ray FEL facility expected to be lasing to users at the end of 2017. Three gap-movable SASE Undulator Systems are designed to produce FELs with tunable wavelengths from 0.05 to 5.2nm.*,** A total of 91 5m long undulator segments and phase shifters were magnetically tuned respecting tight specifications. Magnetic field hysteresis effects due to the gap shift of the Undulator System while changing the FEL radiation wavelength may impact the machine's operational mode. We report on these effects by either opening or closing the gap while performing field integrals measurements with moving wire technique. The undulator segments show negligible magnetic hysteresis and are expected to be operated with no influence to the FEL and beam trajectories in either feed forward or feed backward mode. The phase shifters show first field integrals hysteretic behavior of few G.cm which is comparable in magnitude to the allowed total field integrals and can be associated to the magnetization of the yoke structure. Phase shifters are magnetically tuned for that the feed forward mode (opening gap) fully satisfies the XFEL. EU magnetic specifications for beam operation. PB - JACoW CP - Geneva, Switzerland SP - 522 EP - 524 KW - ion KW - undulator KW - FEL KW - radiation KW - electron DA - 2018/02 PY - 2018 SN - 978-3-95450-179-3 DO - 10.18429/JACoW-FEL2017-WEP054 UR - http://jacow.org/fel2017/papers/wep054.pdf ER -