TY  - JOUR
AU  - Tomin, Sergey
AU  - Kaiser, Jan
AU  - Lockmann, Nils Maris
AU  - Wohlenberg, Torsten
AU  - Zagorodnov, Igor
TI  - Undulator linear taper control at the European X-Ray Free-Electron Laser facility
JO  - Physical review accelerators and beams
VL  - 27
IS  - 4
SN  - 2469-9888
CY  - College Park, MD
PB  - American Physical Society
M1  - PUBDB-2023-04158
SP  - 042801
PY  - 2024
AB  - Undulator tapering controls the resonance properties of the Free-Electron Laser (FEL) amplification process. Energy losses in an undulator, caused by synchrotron radiation and wakefields within the undulator's vacuum chamber, determine the undulator's linear taper. Synchrotron radiation contribution can be calculated analytically, while calculating wakefield energy loss necessitates a beam current profile.We introduce a system for the automatic estimation of wakefield energy loss, which leverages non-invasive THz diagnostics, a current profile reconstruction algorithm enhanced with machine learning, and a recently developed analytical wakefield function for the undulator beamline. The effectiveness of this approach was validated by directly measuring wakefield-induced electron beam energy loss in the European XFEL's undulator section.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:001223197200003
DO  - DOI:10.1103/PhysRevAccelBeams.27.042801
UR  - https://bib-pubdb1.desy.de/record/587132
ER  -