GTS meeting 5 02 17

Attempted to run at 1 mA

1. Ran for few seconds before a HV arc. QE dropped by a factor of 2.
2. Ran again for 1.5 hours with ion-precipitators on (?) before a HV arc. QE dropped by another factor of 2.

Down Monday – Wednesday. List of Tasks

1. Degas dump with NEGS at 2 Amps on for ion pumps to take vacuum load
2. Change ND filter from ND1 to ND3 and mount on Servo two for EPICS control
3. Re-activate photocathode with 3 mm active area
4. Instrument wire scanner
5. Install WiFi access point and enable JMenu on PC in GTS cave
6. Why is Dump/FC picoammeter reading is noisy?
7. Hi-pot VIPGT06
8. SCAM VL LINE SYNC frequency is not 60 Hz?
9. Put ND filter in front of ITVGT06 and mount camera on the floor.

Ion Precipitators

1. ion collectors and anode current
2. The downstream ion collector was wired incorrectly
3. This is a sketch of the internals of the downstream ion collector VICGT06
4. 
5. These are Cornell's results
6. 
7. Grames paper on anode bias: Media:Grames_PST07_final.pdf
8. Pozdeyev PAC 2007 ion trapping: Media:Pozdeyev.PDF
9. Cornell PRAB paper on ion clearing electrodes: Media:Cornell ion colelctors PhysRevAccelBeams.19.034201.pdf
10. Gabriel's calculation (POISSON model) of the voltage needed in upstream ion collector (VICGT04, wire sticking out of the spool piece): Media:Ion collector VICGT04 wire stikcing out of spool piece.pdf
11. CEBAF vacuum during 1 mA run
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13. GTS vacuum 1 mA run April 28 2017
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15. GTS 1 mA run also tripped 1.5 hour July 11 2016
16.