This document contains abbreviated lists of tasks for starting or stopping a photoinjector run. It assumes that the user knows what each term means.

Outline:

Startup I: Warm up laser and regen

Startup II: Warm up RF systems

Startup III: Put laser on the cathode

Startup IV: Prepare for run

Startup V: Propagate beam

Shutdown

1. Check water flow (20 psi) on main pressure gauge.
2. Turn key on Antares main power supply on.
3. Power on the Antares control box.
4. Make sure the back door of the power supply is closed with tape.
5. When resistivity shows at least 2.6 MOhm, turn lamps on.
6. If the resistivity does not go up, turn the valve in the power supply front panel and wait until resistivity goes up t0 2.6 MOhm and then close the valve fully. Then turn counterclockwise by 90 deg for normal flow.
7. Turn on 2 scopes, Gentec power meter, and detector above the table.
8. Power on white switch on regen control box.
9. Turn on PU 610H AC Power (red Switch).
10. Turn on regen control box with key.
11. When red light goes off, set regen triggering to external.
12. Insert mirror 27 in beam path out of Antares.
13. After about 20-30 minutes resistivity should stabilize at 1.9 MOhm and power should read 21-22 Watt.

1. Turn on Neslab unit in control room and change set point to 54°C.
2. Check water level in gun Neslab unit and fill if necessary.
3. Turn on gun Neslab unit.
4. Check water level in linac Neslab and fill if necessary.
5. Plug in booster pump.
6. Turn on klystron cooling water.
7. Check that flow gauge reads 7-8 gpm.
8. Turn on modulator power switch.
9. Enable 3 interlock switches.
10. Increase 3 variacs slowly, staying below labeled maximum current at all times, until they stabilize.
11. Turn on 4 RF control boxes in rack. Leave the HV key switch OFF.
12. Check sulfur hexafluoride pressure and fill if necessary.
13. Check variac currents again after about 20 minutes.

1. If engineering laser is running, turn off interlock box and remove beam pipe
2. Reset timing box and lock again.
3. Check for beam pulse on first scope.
4. Open Antares shutter on control panel.
5. Check Gentec power meter reading (nominal 1.5 W).
6. Reduce power level with half-wave plate 24 until Gentec reads 200 mW.
7. Close shutter and remove mirror 27.
8. Insert portable power meter after fiber and turn on the controller.
9. Open shutter and adjust fiber mount in x and y to optimize power reading (about 120 mW). Don’t touch z!
10. Increase power level to 400 mW with half-wave plate 24.
11. Remove power meter and observe spectrum on second scope.
12. Optimize spectral width using fiber mount and/or half and quarter wave plate and/or cavity length.
13. [Optional: Place power meter after regen and open regen shutter (should be at least 40 mW). Then block beam, place power meter in green (should be about 5 mW).
14. Adjust Stanford box 2 for maximum gain (in steps of 10 msec). Be careful Stanford box 1 changes the CO2 delay (in steps of 7 nsec)
15. Close regen shutter and notify personnel in bunker that laser is coming.
16. Remove power meter, open shutter.
17. In bunker, turn on power meter and scope, connect them, and place meter just before beam entry into beamline.
18. With scope on 50 mV/div, optimize power reading with first mirror on UV table and/or crystal angle knobs (the closest knob isn’t useful). Calibration is 40uJ/50mV
19. Remove power meter and turn off.
20. Center beam on the beamline window using white (UV) card; adjust with second to last mirror on UV table.

1. Turn on solenoid power supply.
2. Turn on solenoid cooling water.
3. Turn on crate in bunker.
4. Turn on power amplifier for linac RF signal (on floor below gun).
5. Open manual gate valve after gun.
6. Clear bunker and lock.
7. Open mini-bunker, clear, and lock.
8. Turn on magnet power supplies (10 quads, steering magnets, degausser supply, 4 trim coils, chicane).
9. Switch on Breaker 25 in the wall panel.
10. Turn the key switch of the HV unit upstairs to REMOTE.
11. Check variac currents.
12. Turn on control room crates.
13. Turn on scope and connect to linac and gun reflected signals.
14. Switch on the high-voltage power unit.
15. Set klystron voltage level to about 30 kV by running “HVPS Control” vi.
16. Push “HV on” button on the power unit and look for blue light.
17. Turn on main trigger switch. If you don’t see traces, figure out what’s wrong.

1. Ramp up klystron voltage slowly to 38 kV, observing traces, and watch for beam on Screen 3.
2. Reduce water temperature to 52°C.
3. Set solenoid current to about 180-190 A and toggle steering magnet supplies.
4. If beam is far off center, adjust with steering magnet 1.
5. Center beam within gun using remote-control mirror and low-level phase knob.
6. Adjust low-level RF phase for best beam (+20 units from blowout). (+ is negative direction on RF phase)
7. Open gate valve after linac.
8. Check beam alignment on Screen 5 and adjust with steering magnets 2 and 3.
9. Using the chicane control, turn off trim coils and switch to dipole mode. Ramp current until energy readout is about 11 MeV and wait for beam to appear. If necessary adjust beam up/down with steering magnet 3.
10. Adjust linac phase for minimum energy spread and note final energy.
11. Bring current to zero, degauss, and return to chicane mode with autotrim.
12. Center large beam on Screen 8 using steering magnets 4 and 5.
13. Make sure valves before and after folding box are open AND valve on side of folding box is closed.
14. Focus on Screen 12 (aperture in folding box) using quads 4-7. If quads steer, correct before the quad with steering magnets and compensate after.
15. Steer through hole in aperture with SM 6 and center in Screen 9 using steering magnet 9. If the power supply is close to maximum output, play with SM 5 and 6 to compensate.
16. Focus on IP strong phosphor and then weak phosphor using last 3 quads.
17. Steer precisely with steering magnet 7 if needed, or with 8 for large changes.

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Switch off interlock power (circuit breaker 25 on wall panel).
Switch off all magnet power supplies in two racks.

Open bunker door.
Turn off solenoid power supply.
Turn off control crate under ICT.
Unplug linac water booster pump.
Close solenoid cooling water valves.
Turn off gun heater control.
Turn off linac signal amp.
Close manual gate valve after gun.
Return to control room and turn off Neslab water pump.

Turn modulator variacs to zero.
Turn off main power switch on modulator box.
Turn off four boxes in control rack.
Close cooling water valves.