Gun turn on plan and dates
A. Brachmann, P. Emma, J. Frisch, R. Akre, M. Stanek, P. Miller
(Draft 10/16)
1. Expected date of PPS certification for injector vault:
2. Completion of BAS for injector:
3. Completion of Laser Heater installation:
4. Full operations shift staffing:
10/25
10/27
10/31
11/3
5. Earliest possible VVS’s turn on:
10/27
6. Software and LLRF issues:
ongoing
1. Check out of software, trigger system, LLRF system
2. Calibration of RF levels, checkout of PAD’s
7. Items to be checked w/o high power RF
1. Verify Network operation
2. Check out of all actuators (except gun valve)
3. New chicane magnets power supply
4. Verify VCC operation
5. 20-6 high power interlock check
6. Verify white light cathode camera image
– Frisch
– Frisch/Akre
begin 10/27
– Controls group
– Operations
– Operations
– Laser group
– Frisch/Akre
– Brachmann
8. Turn on of high power RF for L0A and L0B
With Gun Valve closed:
1. Klystron Phasing?
2. High Power RF calibration, need beam for this
Start strip chart of GTL and L0A/L0B vacua
3. Turn on RF to L0A/L0B (processing)
(normal Power, may take a few shifts, at least two)
4. Turn on of RF to TCAV (processing)
(normal Power, expect one shifts)
5. Verify vacuum conditions in L0A/L0B
11/3
9. Open Gun valve if GTL vacuum is in mid 10-9 Torr range
10. Monitor and check the following (for details see Paul’s script)
Initial checkout of the gun system without power and gun valve closed:
1. Gun vacuum (113, 221, etc.),
2. Gun temperatures,
3. Gun cooling water loop
4. Configs loaded
5. Standardize Quads, Bends, BXG
6. Gun RF feedback and amplitude feedbacks
7. Check gun body temperature
11/3 or 11/4
11/4
11. RF processing of Gun:
 General processing procedure:
o First process gun with L0A/L0B off. Then turn off gun, close gun valve, turn on
L0A/L0B to full power, when stable open gun valve and increase gun to full
power.




Processing details:
Setup the peak power analyzer in RF Hut to make absolute power measurements of the
gun forward and reflected waveforms. Enter the following calibrations:
o Gun fwd: 80.23 dB
o Gun ref: 80.44 dB
Start strip charts for the gun and waveguide vacuum. Load the file
GUN_VAC_April24_2008.stp.
Wait until the gun vacuum is in 10-9 torr scale before opening gun valve starting
processing.
1. If GTL vacuum is in mid 10-9 torr range, open Gun valve
2. Verify gun vacuum (<10-9 Torr w/o RF)
3. Take white light image of cathode before RF turn on. Setup a white light image of the
cathode using the Profile Monitor GUI to monitor the cathode surface during conditioning.
Regularly save images to e-log. Note: The white light image can’t be seen with the gun
valve closed.
4. Insert YAG01 to monitor the dark current.
5. Now is the time to turn on klystron 20-6
Begin processing with low rf power and increase in small steps while keeping the gun
vacuum below 5x10-8 torr. Wait for the vacuum to recover to the 10-9 range before
making next increase. Make sure the gun temperature control is working.
6. Measure klystron forward power using peak power analyzer:
Monitor gun vacuum using sun ray terminal in RF hut
Check gun reflected power to verify gun is in tune
Ramp up klystron power slowly, process gun if vacuum activity occurs
7. Proceed processing to 25.5 MW
Final klystron fwd power should be 25.5 MW, 1.2 us, Gun Fwd should be 11 MW
(one to two shifts)
8. If RF breakdown occurs, lower power, take a white light cathode image, leave white
light image running, keep an eye on it
12. Run first beam


1. Center beam based on VCC (feedback on)
 first time laser is needed
2. Put beam on YAG 02
3. Schottky/QE scan
4. Calibrate gun energy using BXG (Gun at 6 MV)
5. Schottky/QE scan
6. Take white light image
7. Take QE image (Solenoid imaging)
8. Verify beam energy on BXG
Measure gun energy and energy spread
o Turn on BXG using Spectrometer GUI
o Adjust SOL1 to minimize horizontal size (energy spread) on YAGG1
o Measure beam energy vs. the DAC delay to check timing
o Measure beam energy
Gun energy measurements:
o Turn off gun and injector launch feedbacks
o Turn on BXG, make sure the BXG trim is off.
o Measure beam energy and compare with gun RF setpoint
o Scan beam energy vs. RF timing delay, verify good laser-rf timing
o Measure energy and energy spread vs laser phase for nominal and other iris
diameters
o Restore all changes, turn off and standardize BXG (with TRIM supply OFF, then
switch TRIM ON to -1.06 A)
9. Check peak power trip setting
10. Proceed with phasing of L0A/B, TCAV etc.
13.
Proceed with injector start up according to Paul’s script …
14.
Follow 250 pC tune up procedure to optimize gun