A Quasi-Periodic Elliptically Polarized Undulator at the National Synchrotron Light Source II

Marco Musardo, Peter Cappadoro, Oleg Chubar, Todd Corwin, David Harder, Yoshiteru Hidaka, Charles Kitegi, Jim Rank, Toshiya Tanabe, Schaa, Volker RW (Ed.), Tavakoli, Keihan (Ed.), Tilmont, Manuel (Ed.)
A 2.8 m long quasi-periodic APPLE II type undulator has been commissioned at the National Synchrotron Light Source II (NSLS-II) for the Electron Spectro-Microscopy (ESM) beamline in the framework of the NEXT (NSLS-II Experimental Tools) project. It provides high brilliance photon beams in circularly and linearly polarized radiation from VUV to soft X-Rays. The mechanical structure implemented to achieve the quasi-periodicity in the magnetic field profile is described together with the
more » ... on techniques utilized to correct the undesirable phase-dependent errors. The final magnetic results are presented as well as the spectral performance of the device. Although this EPU (Elliptically Polarizing Undulator) was procured as a turn-key device, the vendor was only responsible for the mechanical frame and the control system. Sorting and assembly of the magnet modules and the magnetic field tuning - Virtual Shimming and Magic Finger - were performed at the NSLS-II Magnetic Measurement Lab.
doi:10.18429/jacow-medsi2018-tuph26 fatcat:ek4volivwrgspkfrsqwn7jk6di