XFEL: Milestone for superconducting undulator
Milestone for superconducting undulator

Undulators like this one cause highly accelerated electrons to emit intense and brilliant X-ray light. European XFEL is currently testing superconducting undulators in order to be able to offer users even better conditions for their research in the future.
The strength of the magnets of an undulator determines the tunability of the photon energy range available for experiments. The Undulator Systems Group of European XFEL has started different activities in collaboration with Deutsches Elektronen-Synchrotron DESY to allow the implementation of superconducting undulators into the European XFEL in the upcoming years. The contract for superconducting undulator pre-series module (S-PRESSO) consisting of two pair of coils and a phase shifter has been assigned to Bilfinger Noell GmbH. Now, a European XFEL team at the Karlsruhe Institute for Technology has tested a 30-centimeter-long mock-up superconducting coil designed and build by Bilfinger Noell GmbH. The magnetic field of the S-PRESSO mock-up has reached 2 Tesla, which is larger ever reached before in such undulators.

Comparison of a superconducting undulator (SCU) with permanent magnet undulators for a beam stay clear/vacuum gap of 5 mm. Superconducting undulators (SCU; blue line) have a higher magnetic field than undulators made out of permanent magnet (PMU: permanent magnet undulator; IVU: permanent magnet undulator in vacuum; CPMU: cryogenic permanent magnet undulator). The tested superconducting undulator mock-up has a period length of λ=18 millimeter and a magnetic gap of 6.5 millimeter. The star shows the high performance of the S-PRESSO mock-up (adapted from https://www.frontiersin.org/articles/10.3389/fphy.2023.1204073/full).
Further Information:
Superconducting undulator activities at the European X-ray Free-Electron Laser Facility
https://www.frontiersin.org/articles/10.3389/fphy.2023.1204073/full
Towards a Superconducting Undulator Afterburner for the European XFEL
https://xfel.tind.io/record/2688?_sm_au_=iVVt4kLf4Jj9qS464jRVNK7TN2K23
Scientific contact:
Sara Casalbuoni
Undulator Systems Group
Email: sara.casalbuoni@xfel.eu