Undulator Metrology Catherine LeCocq, SLAC October 27, 2005

1. Undulator MetrologyCatherine LeCocq, SLAC October 27, 2005 • Support Undulator Hall Construction • Develop and Test Fiducialization Procedures • Develop and Test Monitoring Systems • Plan Assembly of Girders • Plan Tunnel Installation Sequence • Alignment Possibilities after Installation

2. Support Undulator Hall Construction • Coordinate Systems • NAD83-State Plane Coordinate System (SPCS-CA Lambert Zone 3 or 0403), see AEG web page: http://wwwgroup.slac.stanford.edu/met/Align/LCLS/LCLS.html • ESD 1.9-106 (Catherine LeCocq) - Height Systems for LCLS Construction • Outside Monumentation • ESD 1.9-107 (Brian Fuss) - LCLS Alignment Construction Requirements • Instrumentation • GPS/RTK using SLAC base station • Total Stations • Automatic Levels

3. Fiducialization Procedures • Undulator • “Undulator Tuning Procedure”, by Zack Wolf • “Undulator Fiducialization Procedure”, by Yurii Levashov • Quadrupole • “Quadrupole Fiducialization Procedure”, by Zack Wolf • Beam Finder Wire • “BFW Fiducialization Procedure”, by Zack Wolf and Eric Lundahl See “Undulator Alignment and Motion” Internal Review, October 20-21, 2005

4. Bench Set-up for Undulator Tuning • Extract from Yurii Levashov: • Alignment to the bench. First step - by conventional tools (±0.2mm); second with the use of capacitor sensors (±10µm). Reference plates for initial alignment to the bench and as capacitor sensor home positions (ordered). • Hall probe measurements to find magnetic axis, i.e. magnetic reference (±5µm random error). • Coordinate transfer from magnetic to mechanical references. Pointed magnets as intermediate reference.

5. Vibrating Wire System under Construction Extract from Zack Wolf: A quadrupole will be centered on a wire to 10 microns. The wire will be located relative to tooling balls to 15 microns. All tooling balls will be located to 10 microns. The overall accuracy in x and y will be better than 25 microns. The magnet pitch and yaw will be smaller than 1 mrad.

6. Undulator Quad BFW Loose End: BFW Solution Fiducialization Steps: 1) Locate wire relative to local fiducials (optically): 25 um 2) Locate local fiducials relative to outside tooling balls (CMM): 15 um Out: The beam goes through a small beampipe making a smooth transition to external beampipes In: Wires are inserted into the beamline. The whole girder is moved to scan the wires across the beam. PRD 1.4-004 Repeatability of positioning wires: 80 um in X, 30 um in Y Extract from Zack Wolf

7. LCLS Magnetic Measurement Facility (MMF) • Construction: SLAC Bldg 81 • LCLS-TN-04-1(SLAC-TN-05-020, February  2005): "Requirements for the Construction of the LCLS Magnetic Measurements Laboratory“, Z Wolf & R. Ruland. • PRD 1.4-002: "Magnetic Measurements Facility Requirements“, R. Ruland & Z. Wolf. • Breakout Session 4 at 3:45PM: “Magnet Measurement Facility Status”, J. Sevilla. • Specification • LCLS-TN-04-8 (SLAC-TN-05-017, August  2004): "Requirement for the LCLS Undulator Magnetic Measurement Bench“, Z Wolf.

8. Some MMF Facts and Updates Leitz Reference Model 45129 CMM manufactured in Wetzlar (Germany)is on order and should arrive mid February. Up to now, the 3 cranes in MMF are still rated @ 2000 kg. CMM weight capacity is now 3000 kg. The original order requested only 2250 kg. CMM measuring range is 0.9 x 1.5 x 4.5 meters. CMM resolution is 0.1 microns or 0.000004 inches. CMM spatial accuracy is a formula based on L, the length measured in mm: 2.0 microns + L/350. There will be some special machine tuning @ the manufacturers site in Germany in December. Machine will be tuned for the undulator segment weight and location on the CMM. After tuning, the expected accuracy for the undulator segment should be upgraded to: 1.5 microns + L/500. Prepared by Eric Lundahl

9. A Reference Reference B 1 33 Monitoring System: WPS • Two wires (one above the other), stretched along the entire Undulator • Four wire position monitors will be installed on each of the 33 girders. • The system monitors X-pos, Y-pos, Pitch, Yaw and Roll with respect to the two wires on a sub-micrometer scale and continuously over time. • A system performance test is under operation at SLAC in a real set up with two 30 meter wires and 14 Wire Position Monitors. The results are encouraging e.g. Readout resolution < 100 nanometer. Prepared by Franz Peters

10. Monitoring System: WPS Studies • Long distance wire R & D • Until now, WPS was operated with wires up to 60 meter length. • Parameter, like signal attenuation or transversal wire oscillation frequency varies with the length of the wire. • A new set up with one roughly 130 meter long wire is now installed and first measurements were done. • Engineering and Integration of WPS into the Undulator system • Upcoming, final layout of the girder reflects to mechanical components of WPS and needs redesign of some interface components. • Connection of Quadrupole, BPM or BFW with WPS is under review. • Electronic Sub-stations of WPS and the distribution at the Undulator hall is designed. Prepared by Franz Peters

11. Monitoring System: HLS • Extensive Tests of the Sensors and HLS. • Identifying error sources and developing solutions for them. • Dielectric constant (e) of water is not stable – routine calibration • Biased readings at some points – new DC-DC converter • Influence of temperature differences – half filled pipe system – correction for pot expansion – corrections for e change • Earth Tides – computation of a model • During the stay of the Engineers from BINP (Novosibirsk) the sensors have been tested and the last changes have been decided. • First articles have been ordered and will arrive in January. Prepared by Georg Gassner

12. Monitoring System: HLS-Girder Integration • Three capacitive and one ultrasonic sensors per girder • Reliable determination of height, roll and pitch • Absolute measurements • Calibration of the system • Controlled measurements • 2 inch stainless steel pipes to connect the pots for optimal damping and maintenance • All sensors are connected with TCP/IP (IEEE 802.3af) • Following a standard (off the shelf products) • Power supply included • Each sensor communicates independently from all others Prepared by Georg Gassner

13. Girder Assembly • Prerequisite • All necessary components fiducialized • Stands aligned in all staging areas • Outside MMF (possibly in Building 750) following the SPEAR3 Approach as suggested by Richard M. Boyce • Station 1 Prepare Girder: Mount CAM wedges under girder • Station 2 Component Installation, part 1 • roll-away slides, component supports • HLS & WPM components • undulator vacuum chamber • Station 3 Component Installation, part 2 • quadrupole, BFW and BPM • Station 4 Wiring / Plumbing • In the Controlled Environment of the MMF • Station 1 Optical Alignment • Station 2 CMM • Storage

14. Tunnel Installation Gather all fiducial data and perform tunnel network design Install tunnel monuments (floor and wall) Survey tunnel network Mark floor for anchors Align floor plates Re-survey tunnel network Align girder stands Survey girders ANL Model

15. Tunnel Network Simulation (LEGO/SIMS) 49 Points – 17 Laser Tracker Set-ups sD = 30 μm sh = 30 μm / D sv =50 μm /D sdh = 50 μm W23 sz = 22 μm sx = 47 μm sy =46 μm

16. Alignment after Installation Loose End Problem Monitoring System Calibration Intra Girder Alignment Verification

17. End of Presentation