FEL SCU development at APS/ANL E.Gluskin for the APS/ANL LCLS SCU Team Mar. 3, 2016

Outline SCU developments at the APS: Motivation APS/ANL LCLS SCU Team APS SCU technical facilities SCU fabrication process SCU assembly process Characterization of SCU magnetic performance Summary

Development of SCUs at the APS Activity Years A proposal of the helical SCU for the LCLS 1999 Development of the APS SCU concept 2000-2002 R&D on SCU in collaborations with LBNL and NHFML 2002-2008 R&D on SCU0 in collaborations with FNAL and UW-Madison 2008-2009 Design (in the collaboration with the BINP) and manufacture of SCU0 2009-2012 SCU0 installed into the APS storage ring December 2012 SCU0 is in routine user operation Since February 2013 SCU1 installed into the APS storage ring and is in user operation April 2015 FEL/LCLS 1.5-m long prototype designed, built and successfully tested October 2015

Performance comparison: SCU and Hybrid Undulator at the APS Brightness Tuning Curves (SCUs1.6 cm vs. UA 3.3 cm vs. Revolver U2.3 cm & U2.5 cm) Tuning curves for odd harmonics of the SCU and the “Advanced SCU” (ASCU) versus planar permanent magnet hybrid undulators for 150 mA beam current. ASCU is Nb3Sn undulator with optimized performance. The SCU 1.6 cm surpasses the U2.5 cm by a factor of ~ 5.3 at 60 keV and ~ 10 at 100 keV. The tuning range for the ASCU assumes a factor of two enhancement in the magnetic field compared to today’s value – 9.0 keV can be reached in the first harmonic instead of 18.6 keV.

Budker Institute of Nuclear Physics 1997 1996 2000 2001 2000 1979 Development and production of SC magnets at Budker INP 2005 2004 Mezentsev Nikolay Budker Institute of Nuclear Physics 2006 2002 2002 2012 2013 2002

LCLS SCU APS Team Yury Ivanyushenkov – head of the team Joel Fuerst – cryogenic design, project management Yuko Shiroyanagi – thermal and mechanical analysis Quentin Hasse – epoxy impregnation, vacuum Chuck Doose – magnet measurements, system assembly Matt Kasa – magnet windings, magnet measurements, controls Sue Bettenhausen – magnet winding, assembly Engineering design support: E.Trakhtenberg, D.Jensen D.Skiadopoulos Special tasks: I.Kesgin General support: G.Pile, M.White

APS SCU facilities Magnet winding lab Magnet measurement bench Compressors for cryocoolers Small vertical cryostat

ANL/APS deliverables to SLAC/ANL/LBNL FEL SCU Project Design and fabrication of the cryostat Design and fabrication of NbTi 2.1-cm period, 1.5-m long undulator. Assembly/integration of NbTi undulator and the cryostat Design and fabrication of beam vacuum chambers Design and fabrication of the magnet measurement system compatible with the small aperture undulators Assembly/integration of Nb3Sn undulator and the cryostat Cryogenic and magnetic characterization of both undulators at the APS SCU facility

SCU: assembled cryostat

SCU: inside the vacuum vessel Cryocoolers 1st thermal shield

SCU: under 1st thermal shield Current leads

SCU: under 2nd thermal shield – cold mass Liquid He vessel Thermal links Liquid He plumbing

SCU: undulator and vacuum chamber Thermal shields

Undulator coils and vacuum chamber

SCU1 undulator magnet 1.08-m long, 1.8-cm period Highly controlled and precise winding - key to the magnet performance

LCLS SCU magnet’s cores and winding

Epoxy impregnation Oven inside: 1.2mx1.5mx3.7m Mold in the oven

LCLS SCU in the large vertical cryostat: quench training and magnet measurements Current, sensors leads Linear stage for the Hall probe scan Undulator magnet

LCLS SCU assembly Undulator assembly Cold mass assembly Cold mass before loading in the cryostat Cold mass in the cryostat on Kevlar loops

Magnetic measurements of the LCLS SCU SCU warm-sensor concept Scanning Hall probe: Specially developed three-sensor Hall probe (attached to carbon fiber tubing and driven by linear stage) to measure By , Bx , and Bz simultaneously. On-the-fly Hall probe measurements (2 cm/s, Δz 0.2 mm, typical z range ±100 cm) to determine local field errors and phase errors. Stretched Wire Coil: Stretched wire rectangular, delta and ‘figure-8’ coils to determine static and dynamic 1st and 2nd field integrals. Coils can be translated along x axis approximately ±0.2 cm to measure integrated multipole components. SCU horizontal measurement system Magnetic measurement system showing 3.5 m linear stage with the SCU cryostat located on the far end of the stage. The system can be configured for Hall probe or stretched-wire measurements without warming the cryostat.

Helical SCU – next step Concept of a new cryostat (Joel Fuerst) Short prototype on the winding machine

Summary APS developed strong expertise in the design and construction of NbTi- based planar SCUs. It has the dedicated facility for construction and characterization of SCUs. APS SCU team acquired and developed all theoretical and technical tools needed for SCUs design and construction. Two SCUs are successfully operating at the APS. APS SCU team for the first time designed, built and characterized SCU that meets or exceed all FEL undulator specifications. APS team worked closely and productively with SLAC and LBL SCU team to ensure the successful completion of the project.

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Backup Material – SCU’s operational statistics Calendar year APS delivered SCU0 operating SCU0 down SCU1 operating SCU1 down 2013 4872 h 4169 h 20 h 2014 4927 h 4410 h 193 h [1] 2015 4941 h 4759 h 0 h 2984 h [2] 1 h Total 14740 h 13338 h 213 h 2984 h Total number of SCU0 self-quenches is 5. E-beam has never been lost due to quenches. [1] November: Partial loss of one cryocooler capacity [2] Installed in May; operated May – December 2015 Go to "View | Header and Footer" to add your organization, sponsor, meeting name here; then, click "Apply to All"