Status of the Undulator Program at the Advanced Photon Source* with Efim Gluskin

Monday 27 May 2019, 13:15 → 14:15 Europe/Stockholm

MAX III (MAX IV)

More than 60 undulators currently operate at the Advanced Photon Source (APS), delivering bright x-ray beams to APS users. The majority of these devices are hybrid permanent undulators. However, there are also five electromagnetic undulators; three of them are superconducting undulators (SCUs), two are planar SCUs, and one is a helical SCU. Since 2013 there has been at least one SCU in operation at the APS, and through all six years, the APS SCUs have operated with predicted or better than predicted radiation performance and with 99% availability. Over the next three years the APS undulator team is facing extremely challenging tasks. All existing undulators have to be either rebuilt or retuned, and several new unique devices have to be designed and built. Particularly challenging are the new SCUs. The present planar SCUs are comprised of ~1.1-m-long magnets, each operated within a 2-m-long cryostat, while the planar SCUs for the upgrade will have ~1.8-m-long magnets that will operate within a 5-m-long cryostat. The long cryostat will support the operation of two SCUs in either an in-line configuration or a canted arrangement. Another great challenge is the development and construction of an arbitrary polarizing SCU, called SCAPE. The prototype of such device is currently under development. Progress is also being made in the development of a planar SCU wound with Nb3Sn superconductor. A Nb3Sn SCU is being designed with two 1.3-m-long magnets within a 5-m-long cryostat, and installation on the APS storage ring is planned for 2021. Along with the cryogenic and magnet systems, the supporting systems, which are required to verify the alignment of the undulators and the magnetic field under cryogenic operating conditions, are being developed to meet the APSU requirements. * Work supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-AC02-06CH11357.