Development and operating experience of a short-period superconducting undulator at the Advanced Photon Source

Abstract

A decade-long effort at the Advanced Photon Source (APS) of Argonne National Laboratory (ANL) on development of superconducting undulators culminated in December 2012 with the installation of the first superconducting undulator "SCU0" into Sector 6 of the APS storage ring. The device was commissioned in January 2013 and has been in user operation since. This paper presents the magnetic and cryogenic design of the SCU0 together with the results of stand-alone cold tests. The initial commissioning and characterization of SCU0 as well as its operating experience in the APS storage ring are described.

Development and Performance of Superconducting Undulators at the Advanced Photon Source

“…Over its two years of operation, SCU0 has functioned with better than 98% availability [9]. The sole lengthy interruption of about fi ve days was due to one of the 4K cryocoolers beginning to lose its cooling capacity, causing the He gas pressure to climb to its settings limit.…”

“…The combination provided an excellent opportunity for accurate comparison of the new SC device versus the well-studied standard APS undulator. The results of the comparison [9] are shown in Figure 5. They are in good agreement with the theoretical predictions.…”

“…Black dots/curve: fast feedback system at the APS storage ring is OFF. Red dots/curve: fast feedback system is ON[9]. © 2015 by the American Physical Society.…”

Comparison of Achievable Magnetic Fields with Superconducting and Cryogenic Permanent Magnet Undulators – A Comprehensive Study of Computed and Measured Values

“…At the Advanced Photon Source (APS), superconducting technology was chosen as a means of achieving enhanced undulator capabilities. The first superconducting undulator (SCU), called SCU0, to be installed in the APS storage ring was successfully commissioned in January 2013 [7]. As technology development proceeded, the SCU0 was followed by the SCU18#1 and the SCU18#2, both 18-mm-period undulators with a magnetic length of 1.1 m, in 2015 and 2016, respectively [8].…”

Thermal Model of a Quench in Superconducting Undulators

“…There are currently two 1.1 m long planar superconducting undulators in operation in the storage ring [1]. A steady state (equilibrium) thermal model for a planar SCU was developed in 2015 [2].…”