1. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 1 LCLS First Prototype Undulator: Mechanical Design and Experience Emil Trakhtenberg Argonne National Laboratory November 14, 2003 Major Design features First Test Results Possible Design Changes Major Design features First Test Results Possible Design Changes

2. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 2 LCLS Prototype Undulator on Magnet Measurement Stand-2

3. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 3 Initial LCLS Undulator Mechanical Specifications

4. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 4 LCLS Prototype Undulator (major design features) 1.Titanium housing made of forged 12” bar. 2.Poles with so-called “wings”. 3.Base of the magnet structure sections made of aluminum alloy (high thermo expansion coefficient) to partially compensate the changes in the magnetization of the permanent magnets with temperature. 4.Only one clamp for each pole and magnet (initially). Clamps are made of titanium. 5.Two ways for the undulator gap adjustment: incremental shims or “push-pull” screws. 1.Titanium housing made of forged 12” bar. 2.Poles with so-called “wings”. 3.Base of the magnet structure sections made of aluminum alloy (high thermo expansion coefficient) to partially compensate the changes in the magnetization of the permanent magnets with temperature. 4.Only one clamp for each pole and magnet (initially). Clamps are made of titanium. 5.Two ways for the undulator gap adjustment: incremental shims or “push-pull” screws.

5. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 5 6.Gap at the ends of the magnetic structure can be precisely tuned by piezo-translators (two on each end). This provide phase control. 7.Out-board area is completely open for the ease of measurements and side shims to tune the field strength along the undulator. 8.Side shims have six bars (initially) made of low- carbon steel. Each bar can be individually adjusted and locked in place. 9.Five cam-shaft movers are used for alignment of the undulator as a whole.

6. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 6 Window inside titanium housing is precisely machined. is precisely machined. Precisely machined grooves in the aluminum magnet array locate pole and magnet positions in the ”Z” direction. Precisely machined grooves in the aluminum magnet array locate pole and magnet positions in the ”Z” direction. LCLS Prototype Undulator Cross Section

7. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 7 Shims or “push-pull” screws can be used for the gap adjustment. Base plate of aluminum alloy was chosen to compensate the change of the field along with temperature change. (It has a high thermal expansion coefficient). LCLS Prototype Undulator Magnetic Structure

8. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 8 Titanium “ears” are ground together finally with poles and then heat treated. Ears extend out from the magnets and fit into the rack grooves. LCLS Prototype Undulator Pole

9. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 9 Strongback Material Selection

10. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 10 LCLS Prototype Undulator Titanium Housing

11. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 11 Titanium Housing Deflection under Magnetic Forces

12. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 12 Prototype undulator is installed on two steel pillars (temporarily). Five cam-shaft movers are used for undulator alignment. (similar to that used for the Final Focus Teas Beam). LCLS Prototype Undulator on the Test Stand

13. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 13 LCLS Prototype Undulator Housing on the Support Stand

14. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 14 Deflection of the LCLS Prototype Undulator

15. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 15 There are three threaded low - carbon bars per shim. Side shims can be installed where needed to compensate phase errors and to adjust the vertical field. Side Shim for the LCLS Prototype Undulator

16. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 16 The short end section of the magnet structure on both ends has slots in the base plate and in the side racks. It allows precise tuning of the pole gap using piezo- translators. End Tuning for the LCLS Prototype Undulator (Overall Device Phase Adjustment Capability)

17. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 17 Fixture for the Magnet Structure Assembly

18. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 18 LCLS Prototype Undulator on Magnet Measurement Stand-1

19. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 19 LCLS Prototype Undulator Planned Design Changes 1. Clamp each pole from both sides. 2. Increase the rigidity of the bottom plate for the magnet structure if still necessary. 3. Compare the price of a round housing and an assembled one. 4. Accommodate the wire potentiometers in the mover design and replace the spherical double bearings with roller bearings having an outside spherical ring. 5. Consider the use of the precisely ground steel shims instead of the brass ones. 6. Shield the motors. 1. Clamp each pole from both sides. 2. Increase the rigidity of the bottom plate for the magnet structure if still necessary. 3. Compare the price of a round housing and an assembled one. 4. Accommodate the wire potentiometers in the mover design and replace the spherical double bearings with roller bearings having an outside spherical ring. 5. Consider the use of the precisely ground steel shims instead of the brass ones. 6. Shield the motors.

20. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 20 Revised Undulator Mechanical Specifications Relaxed tolerances based on prototype manufacturing experience, magnetic measurements, and tuning Will ease manufacturing and assembly

21. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 21 Double Clamped Pole for the LCLS Prototype Undulator

22. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 22 There are two threaded low - carbon bars per shim. Side shims can be installed where needed to compensate phase errors and to adjust the vertical field. Side Shim for the LCLS Prototype Undulator

23. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 23 Assembled Housing for the LCLS Undulator

24. LCLS Prototype Undulator Design LCLS Prototype Undulator Design emil@aps.anl.gov Linac Coherent Light Source Stanford Synchrotron Radiation Laboratory Stanford Linear Accelerator Center LCLS DOE Review, November 14, 2003 Emil Trakhtenberg, ANL 24 Acknowledgments Vladimir Tcheskidov, Nikolai Vinokurov, Efim Gluskin, Mark Erdmann, Oleg Makarov, Thomas Powers, Isaac Vasserman, Patric Den Hartog, Elizabeth Moog, Patric Den Hartog, Elizabeth Moog, Branislav Brajuskovic, Jeffrey Collins. Vladimir Tcheskidov, Nikolai Vinokurov, Efim Gluskin, Mark Erdmann, Oleg Makarov, Thomas Powers, Isaac Vasserman, Patric Den Hartog, Elizabeth Moog, Patric Den Hartog, Elizabeth Moog, Branislav Brajuskovic, Jeffrey Collins.