GTS meeting 3 28 17

• Conditioned Gun at 300 kV with solenoid at 0 to 300 A, left to do it at: 325, 350, 375, and 400 A. Two currents, 350 and 400 A, we attempted before but we will repeat.

• Attempting to center solenoid by moving magnet:

1. Moved solenoid 1.5 mm to beam left - closer to active area at 3:00 o'clock
2. Moved solenoid 3.2 mm (from center) to beam right. In both cases no improvement by looking at beam on ITVGT03 (first viewer) while scanning the solenoid between 10-150 Amps. Beam can be seen on edge of viewer rotating clockwise then drifting towards -45 degrees (lower-right) as solenoid current approaches 150 Amps.

• Magnet was moved back to original center position by S&A. We are waiting on final survey report.

• Attempting to center solenoid by moving active area:

1. Moved active area to 9:00 o'clock, 12 o'clock and 6 o'clock. In the three cases no improvement by looking at beam on ITVGT03 (first viewer) while scanning the solenoid between 10-150 Amps. beam behaved similarly at the four laser positions (including the initial 3 o'clock).

• Laser Newport powermeter is now at the exit window side of the gun

• Laser tables are covered

• Plan for this week (March 27, 2017):

1. Monday, Tuesday and Wednesday: open in morning to install second part of beamline but close in afternoon to run beam
2. Thursday and Friday open all day for beamline bake. Turn ON the extractor gauge in Gun HV Chamber. Use GN2 heater to send 250 C hot gas through the water lines of the FCup to degas.
3. Week of April 3rd: finish bake and instrument beamline

• What we are working on now:

1. Still trying to center the gun solenoid
2. Do we want to keep the anode biased at +280 V all times (and while running beam)?

• Emittance vs Gun HV: media:Emittance_GunHV_3468399.xlsx [1]

• These are the simulation tasks that we should try:

1. Simulate beam rotation at: B=0 G (0 A), B=170 G (50 A), B=340 G (100 A), B=510 G (150 A), B=680 G (200 A), B=850 G (250 A), B=1020 G (300 A), B=1190 G (350 A), B=1360 G (400 A)
2. Simulate emittance vs Gun HV