European XFEL Seminar | Plans for an Helical Afterburner at LCLS II

by Zachary Wolf (SLAC)

Thursday 19 Jan 2017, 14:00 → 15:00 Europe/Berlin

E1.173 (Schenefeld) (European XFEL)

SLAC is presently designing three Delta undulators to be placed at the end of the soft x-ray line of LCLS-II and which will collectively give intense elliptical polarization. We were alerted by the Swiss Light Source that the K value in EPUs can have a strong position dependence, and this has a big impact on the design of the undulators and their alignment tolerances. I will discuss an analytic calculation describing this position dependence of K and the consequences for the undulator design. I will also discuss assembly tolerances on the Delta undulators in order to minimize phase errors. Finally, I will discuss our LCLS-II measurement plans including fitting K vs gap, the phase matching algorithm to set the phase shifter, radiation damage measurements in the tunnel, and how we will deal with the Earth's magnetic field. Host: Joachim Pflüger

Abstract 19012017_EXS_Zachary_Wolf.pdf