LCLS Commissioning P Emma et al LCLS Operations

LCLS Commissioning P. Emma, et al. LCLS Operations Lectures June 7, 2006 LCLS Commissioning 1 Paul Emma@SLAC. Stanford. edu

LCLS Accelerator Schematic 6 Me. V z 0. 83 mm 0. 05 % 4. 30 Ge. V z 0. 022 mm 0. 71 % , b -a L 0 Linac-1 L 9 m rf -25° . . . existing linac 21 -1 b, c, d DL 1 L 12 m R 56 0 X BC 1 L 6 m R 56 -39 mm 21 -3 b 24 -6 d BC 2 L 22 m R 56 -25 mm 2 undulator L =130 m 25 -1 a 30 -8 c Commission in Jan. 2008 SLAC linac tunnel LCLS Commissioning Linac-3 L 550 m rf 0° Linac-2 L 330 m rf -41° Commission in Jan. 2007 June 7, 2006 13. 6 Ge. V z 0. 022 mm 0. 01 % Linac-X L =0. 6 m rf= -160 Linac-0 L =6 m rf gun 250 Me. V z 0. 19 mm 1. 6 % 135 Me. V z 0. 83 mm 0. 10 % DL 2 L =275 m R 56 0 research yard Paul Emma@SLAC. Stanford. edu

Complete & Detailed Optics (cathode to dump) dump cathode L 2 BC 2 L 3 LTU sec-30 muon plug wall sec-21 undulator Full MAD files at: http: //www-ssrl. slac. stanford. edu/lcls/linac/optics/ June 7, 2006 LCLS Commissioning 3 Paul Emma@SLAC. Stanford. edu

LCLS Installation and Commissioning Time-Line Drive-Laser Commissioning undulator hall ready Drive-Laser Install LTU/und. Install linac/BC 2 Install First FEL Light First Spont. Light M J J A SOND J FMAM J J 2006 2007 2008 June 2006 Gun/Inj. /BC 1 Install Commissioning (8/21 – 1/5) June 7, 2006 LCLS Commissioning 4 linac/BC 2 FEL Commissioning LTU/undulator Commissioning Paul Emma@SLAC. Stanford. edu

RF Gun 6 Me. V L 0 a RF section 62 Me. V gun spectrometer Injector Layout L 0 b RF section 135 Me. V Transverse RF deflector L 1 RF section (21 -1 b) main SLAC Linac injector spectrometer sector 20 June 7, 2006 LCLS Commissioning 5 sector 21 Paul Emma@SLAC. Stanford. edu

LCLS Injector Commissioning Dates (’ 06 - ’ 07) July 24: Sector-20 ready for laser installation Aug. 29: Laser installation complete Dec. 18: Virtual cathode fully characterized (ready to install gun) Dec. 19: RF gun installation starts (10 days) + pre-beam checkout Dec. 20 -Jan. 1: Holidays Jan. 2: VVS’s switched on (RF power available) Jan. 12: First laser UV-light on cathode! Jan. 12 -Feb. 4: Electrons in GTL and gun-spect. (RF processing L 0 a, b, L 1, LX) Feb. 5: Beam into L 0 a, L 0 b and down to 135 -Me. V spect. Feb. 20: Beam into main linac (to TD 11 dump) ~June: Take beam down full linac (to BSY SL 2 stopper) June 7, 2006 LCLS Commissioning 6 Paul Emma@SLAC. Stanford. edu

OUT OF DATE Microsoft Project Commissioning Schedule LCLS Commissioning 7 2007 DO W N 2006 DO W N June 7, 2006 Paul Emma@SLAC. Stanford. edu

pass-1 OUT OF DATE pass-2 pass-3 LCLS Commissioning 8 pass-2. . . Paul Emma@SLAC. Stanford. edu 2007 DO W N 2006 DO W N June 7, 2006 pass-1

LCLS Commissioning 9 OUT OF DATE Paul Emma@SLAC. Stanford. edu 2007 DO W N 2006 DO W N June 7, 2006 pass-2. . . pass-3 pass-1

Commissioning Definition and Strategy All components have been installed, aligned, connected, and initially verified by the system engineer, then commissioning starts. Commissioning Sequence (1 -4) 1. Pre-Beam Checkout (tunnel and MCC) Controls/software testing, check cameras, ‘snail’ hunt, etc Magnet polarities, cable connections, verify motion-control, etc 2. Beam-based Hardware and Software Checkout Establish beam transport, RF setup, MPS/BCS tests, etc Checkout of all wires, screens, BPMs, toroids, magnets, etc 3. First-Order Optics: Measurement and Correction Steering, transmission, oscillation data, feedback setup, etc Beta and dispersion matching, beam-base align key quads, etc 4. Full Beam Characterization: Measurement and Correction Measure emittance, energy spread, distributions - correct Measure beam sensitivities, optimize tuning, beam experiments No (serious) emittance measurements until all hardware/software checked out! June 7, 2006 LCLS Commissioning 10 Paul Emma@SLAC. Stanford. edu

Electron Commissioning Organization Project Director J. Galayda Commissioning Don P. Emma Alternating Weekly Run Coordinator One Lead Physicist per shift Shift Physicists June 7, 2006 LCLS Commissioning Controls & System Engineers 11 MCC & Laser Operators Paul Emma@SLAC. Stanford. edu

LCLS Injector Commissioning Day 24 -Hour Cycle (7 days/week, 1/2/07 to 9/1/07, 32 total weeks) DAY SHIFT (8: 00 -16: 00) 1 lead physicist, 1 controls eng. , 1 sys. engineer, 1 LCLS operator, 1 laser operator SWING SHIFT (16: 00 -24: 00) 1 lead physicist, 1 LCLS operator, 1 laser operator OWL SHIFT (0: 00 -8: 00) 1 LCLS operator, 1 laser operator ? June 7, 2006 LCLS Commissioning 12 Paul Emma@SLAC. Stanford. edu

LCLS Commissioning Parameters Parameter Value Comments RF rate 30 Hz in linac (possible short-term 120 -Hz rate in L 0 BC 1 for feedback tests, etc) - 120 Hz in gun for short time to verify full rate Beam rate ≤ 30 Hz e- beam as baseline – possible short term 120 Hz tests in L 0 -BC 1 for feedback tests, etc Drive-laser rate 120 Hz 120 -Hz at all times – shutters provide e- rate as required above Bunch charge 200 -500 p. C depends on QE and diagnostics – some short spans at 10 p. C – later in ’ 07 we explore 1 -n. C Drive-laser pulse length 10 ps fwhm 10 -ps fwhm startup with possibility of 6 -ps at 0. 2 n. C later – early laser tests may provide path to more convenient pulse-length changes Gun gradient Set as goal, although 110 MV/m is adequate in ‘ 07 June 7, 2006 LCLS Commissioning 120 MV/m 13 Paul Emma@SLAC. Stanford. edu

Issues Controls will be mixed (SLC & epics) and capabilities may be limited initially Most High-Level Applications (emittance, bunch length, feedback) must done through MATLAB as a temporary solution Most LCLS physicists not yet experienced in SLAC control room with SLC controls Help from operations group will be needed LCLS Lecture Series + Workshop in Oct. ? June 7, 2006 LCLS Commissioning 14 Paul Emma@SLAC. Stanford. edu

Q = 1 n. C RF f = 120 Hz G = 120 MV/m gex, y = 1 mm Dt = 10 ps I = 100 A E = 6 Me. V Photo-Cathode Gun spec. dipole e- e- UV laser solenoid cathode YAG screens RF gun June 7, 2006 LCLS Commissioning 15 Paul Emma@SLAC. Stanford. edu

RF Gun YAG screen trajectory (BPMs) emittance (+ slice) energy spread (+ slice) bunch length (+ dist. ) charge (+ dark current) YAG screen Transverse RF deflector OTR & wire gun spectrometer Injector Diagnostics OTR & wire main SLAC Linac injector spectrometer YAG & OTR June 7, 2006 LCLS Commissioning 16 Paul Emma@SLAC. Stanford. edu

Injector Through BC 1 Commissioning no laser-heater until ‘ 08 RF deflector June 7, 2006 LCLS Commissioning gex, y and slice 17 E E Paul Emma@SLAC. Stanford. edu

Injector Through BC 1 Commissioning (2) relative bunch length monitors BC 1 E X-band RF June 7, 2006 LCLS Commissioning E slice gey 18 gex, y stopper Paul Emma@SLAC. Stanford. edu

Setup of Linac-1, X-band RF Phases 20 -mm res. BC 1 BPM LX RF phase L 1 RF phase Linac-1 RF phase scan (X-band off, BC 1 bends at 295 Me. V) Linac-X RF phase scan (BC 1 bends at 250 Me. V) set phase to -25˚ 0. 5˚ set phase to -160˚ 0. 5˚ rf gun w ne Linac-1 21 -1 b 21 -1 d June 7, 2006 LCLS Commissioning X Turn on BC 1 energy feedback Switch off BC 2 chicane Use sec-25 RF-deflector to meas. bunch length ( z 1) Adjust S-band RF phase ( 0. 5˚) to set z 1 195 10 mm 19 Paul Emma@SLAC. Stanford. edu

Setup of Linac-2 RF 40 -mm res. BC 2 BPM 5 -mm res. LTU BPM wake-loss scan L 2 RF phase L 2 phase Scan Linac-2 phase & use LTU BPM to find max. wake-induced energy loss across Linac-3 Linac-2 RF phase scan (BC 2 bends at 5. 9 Ge. V, or…) set phase to -41˚ 0. 5˚ L 2 June 7, 2006 LCLS Commissioning L 3 Turn on BC 2 energy feedback Use sec-25 RF-deflector to measure length ( z 2) Adjust L 2 RF phase ( 0. 5˚) to set z 2 20 2 mm Linac-3 phasing is trivial ( 5˚) 20 Paul Emma@SLAC. Stanford. edu

Longitudinal Beam-Based Feedback 0 V 0 gun z 1 z 2 1 2 L 0 1 V 1 L 1 DL 1 June 7, 2006 LCLS Commissioning 2 V 2 L 2 X BC 1 L 3 BC 2 21 V 3 3 DL 2 Paul Emma@SLAC. Stanford. edu

Location of Main Linac Diagnostics 5+ energy spread meas. stations (optimized with small b) 5+ emittance meas. stations designed into optics (Dyx, y) BPMs at or near most quadrupoles and in each bend syst. RF deflectors for slice e and E measurements (L 0 & L 3) rf gun T-cav. L 0 gex, y L 1 . . . existing linac E E June 7, 2006 LCLS Commissioning gex, y T-cav. L 2 X E L 3 E E E 22 gex, y E E Paul Emma@SLAC. Stanford. edu E E

Slice-Emittance Measurement Simulation RF-deflector at 1 MV sy bunch length slice OTR 10 times 135 Me. V quad scanned June 7, 2006 LCLS Commissioning 23 Paul Emma@SLAC. Stanford. edu

Slice-Emittance Measurement Simulation Injector (135 Me. V) with S -band RF-deflector at 1 MV (same SLAC slice-e code used at BNL/SDL) (slice-y-emittance also simulated in BC 1 -center) = meas. sim. = calc. = y distribution = actual DL 1 slice-emit on WS 02 slice-5 June 7, 2006 LCLS Commissioning 24 Paul Emma@SLAC. Stanford. edu

y-slice-Emittance Measurement in BC 1 “Q 21201” scanned ± 20% June 7, 2006 LCLS Commissioning 25 0. 1 mm 3. 9 mm Paul Emma@SLAC. Stanford. edu

Slice ey Measurements at BNL weak quad setting undulators linac (off) 75 Me. V dump linac 75 Me. V dump medium quad setting strong quad setting 200 p. C, 100 A, 75 Me. V Data from DUVFEL at BNL: W. Graves, e June 7, 2006 LCLS Commissioning 26 Paul Emma@SLAC. Stanford. edu

Linac-To-Undulator (LTU) vertical bends energy centroid & spread meas. (OTR) (3 10 -5 & 10 -4) + collimation 4 e-wires, 6 collimators, 1 OTR · · · June 7, 2006 LCLS Commissioning 27 vertical bends horiz. jog 1. 25 m energy diagnostics emit. diagnostics collimators branch points for future undulators Paul Emma@SLAC. Stanford. edu

Slice Energy Spread Measurements in LTU s. E/E 10 -4 LTU at 14 Ge. V with S-band RF-deflector at 24 MV sx 12 mm FEL goal June 7, 2006 LCLS Commissioning 28 Paul Emma@SLAC. Stanford. edu

Summary Injector commissioning starts very soon (Laser: Aug. ‘ 06, Electrons: Jan. ‘ 07) Phase-II of commissioning comes in Jan. ‘ 08 LCLS group will need continual help from operations group LCLS is a 30 -year machine – this is just the start June 7, 2006 LCLS Commissioning 29 Paul Emma@SLAC. Stanford. edu