1 Heinz-Dieter Nuhn 1 Undulator Plans June 2009 FAC Undulator Commissioning Heinz-Dieter Nuhn – LCLS Undulator Group Leader June 8, 2009

2 Heinz-Dieter Nuhn 2 Undulator Plans June 2009 FAC 29 Undulators Installed

3 Heinz-Dieter Nuhn 3 Undulator Plans June 2009 FAC Segment Installation Schedule Undulator Segments are being installed in the tunnel as they finish tuning 1/25/2009 – 3/2/2009 (U25 (SN16) Test installation) 3/3-24/2009 U13 – U33 4/22/2009 U09 – U12 5/13/2009 U06 – U08 6/3/2009 U04 and U05 6/3/2009 Removed U33 for damage check. 6/17/2009 U02, U03, and U33 installation planned. Three plus one more undulators are to be installed Regular Undulator Rotation Program will start after temperature calibration procedure Undulator Segments are being installed in the tunnel as they finish tuning 1/25/2009 – 3/2/2009 (U25 (SN16) Test installation) 3/3-24/2009 U13 – U33 4/22/2009 U09 – U12 5/13/2009 U06 – U08 6/3/2009 U04 and U05 6/3/2009 Removed U33 for damage check. 6/17/2009 U02, U03, and U33 installation planned. Three plus one more undulators are to be installed Regular Undulator Rotation Program will start after temperature calibration procedure

4 Heinz-Dieter Nuhn 4 Undulator Plans June 2009 FAC Undulator Beam Operation Highlights December 13, 2008 First electron beam through undulator vacuum chamber. No extra steering corrections necessary to get 100% transmission to main dump. Pre-beam girder alignment was sufficient. April 10, 2009 First electron beam through undulator segments. Detected FEL beam after 105 minutes, CCD saturation 20 minutes later. December 13, 2008 First electron beam through undulator vacuum chamber. No extra steering corrections necessary to get 100% transmission to main dump. Pre-beam girder alignment was sufficient. April 10, 2009 First electron beam through undulator segments. Detected FEL beam after 105 minutes, CCD saturation 20 minutes later.

5 Heinz-Dieter Nuhn 5 Undulator Plans June 2009 FAC Preset Girder Positions for First Beam The girders were moved in x and y direction before the first beam was sent through the undulator, mostly to align the beam pipes and the quadrupoles as close to a straight line as possible but also to use the off-axis quadrupole fields to compensate for the earth magnetic field. Both corrections were based on measurements provided by the Metrology group. The first beam shot did not need any alignment correction to pass through the undulator beam pipe (remember a 130-m- long soda straw) to the main dump. The maximum orbit error was only about 1 mm. The plot is from J. Welch's girderPositionPlotGui and shows schematically the position by which each of the girders was displaced.

6 Heinz-Dieter Nuhn 6 Undulator Plans June 2009 FAC Checking Undulator K Using YAG Luminescence* 10 or 11 undulators IN, Ipk = 500 A, LH = 200 uJ First and third harmonic of spontaneous radiation as background 3 rd hamrmonic of Spontaneous Undulator Radiation on YAG Crystal E e = 11.1 GeV E e = 11.3 GeV E e = 11.5 GeV E e = 11.7 GeV E e = 11.9 GeV Spontaneous Radiation from Dump Bend Yttrium K Edge at keV equals 3 rd harmonic of undulator radiation at GeV *by J. Welch and J. Frisch Kmax = Kmin = Kavg = Expected Kund = ± More precise bracketing gave Kavg =3.4932± (1.7 ×10 -4 from expected value)

7 Heinz-Dieter Nuhn 7 Undulator Plans June 2009 FAC YAG Screen Image of First Lasing 10 or 11 undulators IN, Ipk = 500 A, LH = 200 uJ First and third harmonic of spontaneous radiation as background FIRST LCLS FEL LIGHT

8 Heinz-Dieter Nuhn 8 Undulator Plans June 2009 FAC Undulator Characterization: 1 st Field Integral U09 Beam Based Measurements Horizontal (I1X) and vertical (I1Y) first field integrals measured by fitting a kick to the difference trajectory as function of undulator displacement Reference Point MMF Measurement

9 Heinz-Dieter Nuhn 9 Undulator Plans June 2009 FAC Measurement of 1 st Field Integral U11 Beam Based Measurements Reference Point MMF Measurement The beam-based measurement relies on the RF cavity BPMS to achieve a 20 nrad measurement resolution of the kick angle inside the undulator

10 Heinz-Dieter Nuhn 10 Undulator Plans June 2009 FAC Alignment Tolerance Verification Random misalignment with flat distribution of widh ± a => rms distribution a/sqrt(3)

11 Heinz-Dieter Nuhn 11 Undulator Plans June 2009 FAC Simulated: Horizontal Module Offset Horizontal Model Offset (Gauss Fit) LocationFit rmsUnit 090 m0782µm 130 m1121µm Average0952µm Simulation and fit results of Horizontal Module Offset analysis. The larger amplitude data occur at the 130-m-point, the smaller amplitude data at the 90-m-point. S. Reiche Simulations 2006 Budget Tolerance 90 m 130 m Simulated Saturation occurred at 90 m Actual Simulation occurred at 68 m Correction factor sqrt (90/68) = 1.15 This brings average to 1.10 mm

12 Heinz-Dieter Nuhn 12 Undulator Plans June 2009 FAC LCLS Tolerance Budget Error Source ii fifi  i f i 130 m(24.2% red.) Hor/Ver Optics Mismatch (  -1) Hor/Ver Transverse Beam Offset µm Module Detuning  K/K % Module Offset in x µm Module Offset in y µm Quadrupole Gradient Error % Transverse Quadrupole Offset µm Break Length Error mm  < <  /  0 <1.56 Tolerance Budget Components

13 Heinz-Dieter Nuhn 13 Undulator Plans June 2009 FAC Girder Stability : Position / Temperature Temperature fluctuations, girder deformation, and ground motion cause changes in Undulator strength, which depends on Temperature Beam trajectory Quadrupole position instability, which causes Changes to the electron beam trajectory (phase errors) Good News: Observed stability of girder positions and temperatures is better than expected. Temperature fluctuations, girder deformation, and ground motion cause changes in Undulator strength, which depends on Temperature Beam trajectory Quadrupole position instability, which causes Changes to the electron beam trajectory (phase errors) Good News: Observed stability of girder positions and temperatures is better than expected.

14 Heinz-Dieter Nuhn 14 Undulator Plans June 2009 FAC Girder Stability During 2008 Winter Break RMS Position Change < 1 µm Alignment Diagnostics System (ADS) Measurements show how much the girder posiiton deviatation from a straight line changed over the period of one week during lab closure.

15 Heinz-Dieter Nuhn 15 Undulator Plans June 2009 FAC Girder 13 Stability During 19h Operation 200 nm Alignment Diagnostics System (ADS)

16 Heinz-Dieter Nuhn 16 Undulator Plans June 2009 FAC Girder 15 Movement (18 h) During ROD (11 h) >1 µm Mechanical Hysteresis Alignment Diagnostics System (ADS)

17 Heinz-Dieter Nuhn 17 Undulator Plans June 2009 FAC Temperature Recording of Girder 16 REPAIR OPPORTUNITY DAY (ROD) SHUT DOWN (UND INSTALLATION) HVAC SETPOINT ADJUSTMENT 50 mK

18 Heinz-Dieter Nuhn 18 Undulator Plans June 2009 FAC Temperature at all Girders Mounted to Undulator On Girder Downstream U23 Center U23 Upstream U23

19 Heinz-Dieter Nuhn 19 Undulator Plans June 2009 FAC K is Adjusted for Temperature Deviations

20 Heinz-Dieter Nuhn 20 Undulator Plans June 2009 FAC Use of (T-)Corrected K Values K ADJUSTMENT RANGE TEMPERATURE CORRECTED K TAPER REQUIREMENT

21 Heinz-Dieter Nuhn 21 Undulator Plans June 2009 FAC Radiation Control and Monitoring Undulator radiation damage is greatly reduced through Machine Protection System (MPS) hardware interlocks that inhibit beam to the undulator hall when PEP/ANL type BLM signals are above threshold Beam loss fiber signals are above threshold Horizontal and/or vertical trajectory is outside ±1mm Comparator toroids indicate beam loss. Any of the upstream profile monitors is inserted More than 1 BFW is inserted or a BFW is moving A regular TLD monitoring program is in place (s. below) A regular undulator circulation program will start soon (s. below) Undulator radiation damage is greatly reduced through Machine Protection System (MPS) hardware interlocks that inhibit beam to the undulator hall when PEP/ANL type BLM signals are above threshold Beam loss fiber signals are above threshold Horizontal and/or vertical trajectory is outside ±1mm Comparator toroids indicate beam loss. Any of the upstream profile monitors is inserted More than 1 BFW is inserted or a BFW is moving A regular TLD monitoring program is in place (s. below) A regular undulator circulation program will start soon (s. below)

22 Heinz-Dieter Nuhn 22 Undulator Plans June 2009 FAC TLD Replacement Program Thermo Luminescent Dosimeters (TLDs) are mounted inside the Undulator Hall and are regularly replaced and evaluated Baseline 10/3/2008 – 12/9/2008 (10 TLDs) Startup 12/12/2008 – 12/17/2008 (12 TLDs) 1 st Undulator 1/28/2009 – 2/4/2009 (15 TLDs) 1 st Undulator 2/4/2009 – 2/11/2009 (14 TLDs) 1 st Undulator 2/11/2009 – 2/18/2009 (18 TLDs) 1 st Undulator 2/18/2009 – 3/2/2009 (48 TLDs) FEL Operation 3/24/2009 – 4/22/2009 (68 TLDs) FEL Operation 4/22/2009 – 5/6/2009 (125 TLDs) FEL Operation 5/6/2009 – 5/27/2009 (128 TLDs) FEL Operation 5/27/2009 – … (128 TLDs) FEL Operation … Latest TLD placements include detection of neutrons and high energy gamma through use of moderators and W and Pb absorbers. TLD volume is expected to taper down after initial observation period. Thermo Luminescent Dosimeters (TLDs) are mounted inside the Undulator Hall and are regularly replaced and evaluated Baseline 10/3/2008 – 12/9/2008 (10 TLDs) Startup 12/12/2008 – 12/17/2008 (12 TLDs) 1 st Undulator 1/28/2009 – 2/4/2009 (15 TLDs) 1 st Undulator 2/4/2009 – 2/11/2009 (14 TLDs) 1 st Undulator 2/11/2009 – 2/18/2009 (18 TLDs) 1 st Undulator 2/18/2009 – 3/2/2009 (48 TLDs) FEL Operation 3/24/2009 – 4/22/2009 (68 TLDs) FEL Operation 4/22/2009 – 5/6/2009 (125 TLDs) FEL Operation 5/6/2009 – 5/27/2009 (128 TLDs) FEL Operation 5/27/2009 – … (128 TLDs) FEL Operation … Latest TLD placements include detection of neutrons and high energy gamma through use of moderators and W and Pb absorbers. TLD volume is expected to taper down after initial observation period.

23 Heinz-Dieter Nuhn 23 Undulator Plans June 2009 FAC TLD Readings at First Undulator LOCATIONWEEK 1 PHOTON [rad]WEEK 2 PHOTON [rad]WEEK 3 PHOTON [rad] U25:ANL-BLM U25: PEP-BLM U25: Back +X U25: Back +Y U25: Back -X U25: Back +Y U25: Front +X U25: Front +Y U25: Front -X U25: Front -Y Recorder Photon Doses about 0.1 rad per week

24 Heinz-Dieter Nuhn 24 Undulator Plans June 2009 FAC SN16 Radiation Damage Test HAS BEEN INSTALLED ON GIRDER 25 DURING BEAM OPERATION

25 Heinz-Dieter Nuhn 25 Undulator Plans June 2009 FAC Dose During Initial X-Ray Operation e-folding length 8.7 m Increased TLD Readings are expected to be predominantly low energy synchrotron radiation, not to cause significant magnet damage [rad]

26 Heinz-Dieter Nuhn 26 Undulator Plans June 2009 FAC Dose During Recent X-Ray Operation e-folding length 8.7 m Increased TLD Readings are expected to be predominantly low energy synchrotron radiation, not to cause significant magnet damage neutron dose at end of undulator line about 100 mrad/week or less

27 Heinz-Dieter Nuhn 27 Undulator Plans June 2009 FAC TLD Readings at End of Undulator Line LOCATIONPhoton Dose over 3 weeks [rad] Downstream U32 without / with 1.6 mm Pb wrap0.52 / 1.84 Downstream U33 without / with 1.6 mm Pb wrap1.38 / 6.37 Downstream (about 2.5 m) U33 without / with W0.62 / 0.05 Downstream (about 2.5 m) U33 without / with Al0.59 / 0.31 U33 Cam Motors CM2 / CM50.00 / 0.02 U33 Horizontal Slide Motor SL10.08 On top of RFBPM Chassis U31 / U / 0.31 Girder Motion Electronics Racks U25 / U29 / U / 0.01 / 0.01 WPM Electronics Racks U25 / U /.08 North Side of Tunnel opposite of U Shielded Electronics

28 Heinz-Dieter Nuhn 28 Undulator Plans June 2009 FAC SN20 Radiation Damage Test HAS BEEN INSTALLED ON GIRDER 33 DURING FEL OPERATION

29 Heinz-Dieter Nuhn 29 Undulator Plans June 2009 FAC Undulator Circulation Program Undulators will be periodically removed from the Undulator Hall to be re-measured at the MMF to check for radiation damage A “test”-undulator was re-measured after several weeks of beam operation. No damage was found. First undulator that participated in FEL run was removed on June 3 and MMF testing has found it to be undamaged Depending on MMF availability, up to 2 undulators per month will be removed from the Undulator Hall for checking After the undulators have been found undamaged they will be reinstalled onto the original girder Undulators will be periodically removed from the Undulator Hall to be re-measured at the MMF to check for radiation damage A “test”-undulator was re-measured after several weeks of beam operation. No damage was found. First undulator that participated in FEL run was removed on June 3 and MMF testing has found it to be undamaged Depending on MMF availability, up to 2 undulators per month will be removed from the Undulator Hall for checking After the undulators have been found undamaged they will be reinstalled onto the original girder

30 Heinz-Dieter Nuhn 30 Undulator Plans June 2009 FAC Undulator tuning and installation close to completion Initial beam operation went extremely smoothly: no tweaking required Temperature and girder stability are well within tolerance Beam loss control and radiation monitoring is in place High radiation levels at initial FEL operation are expected to be predominantly low energy photons that should not generate demagnetization Very low dose levels measured at electronics components Undulator circulation program has started Undulator tuning and installation close to completion Initial beam operation went extremely smoothly: no tweaking required Temperature and girder stability are well within tolerance Beam loss control and radiation monitoring is in place High radiation levels at initial FEL operation are expected to be predominantly low energy photons that should not generate demagnetization Very low dose levels measured at electronics components Undulator circulation program has started Summary

31 Heinz-Dieter Nuhn 31 Undulator Plans June 2009 FAC End of Presentation