Wednesday, January 12, 2022, 16:08 : HV ramped to 30kV, EZL=15kV, EE=-1.5kV

Ramping up to 250A on TGHT, 200A on TBHT. See MassMarkerTest#1 for ramp up values of the thermocouples.

Seeing some beam on FC0, changing magnet settings to Cs to check FC6 then will ramp up.

Thursday, January 13, 2022, 14:22 :  1.3e-10 approximately Cs on FC6. Optimal EE -2700V, slightly higher than standard on EZL.

 Ramping down to Na on the magnet, found 5 pA:

 Started a ramp up to nominal heater values (TGHT-500 A  TBHT-230 A) but too much HV sparking so aborted at TGHT-299 A and TBHT-230 A. Ramped HV down to 16kV to get sparking to slow down.

Ramped quickly back up to 30kV to get FC readings but since there is so much sparking, we decided to ramp everything down and open the vacuum chamber.

PLAN:

1. ramp down heaters, vent vacuum, open chamber.

2. Try to tape the thermocouples up so that they are further from ground.

3. Try to crimp the bottom of the mass marker tubes, and bend them upwards so they aren't facing ground.

4. Add a dedicated ground to the COIL power supply.

From Fernando:

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Monday, January 17, 2022, 09:52: IG1 on. Source PS off. HV Cage removed. - AS
Monday, January 17, 2022, 11:11: Cage on. TGHT/TBHT PS on. - AS

Monday, January 17, 2022, 11:23: PS/ Sources on. - AS

Monday, January 17, 2022, 14:00: HV ramped to 20kV, EZL 10kV, EE, -1500V. Ramping TGHT/TBHT to previous values of 250A/200A.

Monday, January 17, 2022, 16:51 : Back to previous heater values, didn't find any Cs on FC6 so went to Na. Tuned and found the tune the opposite of last time, all voltage wanted to go lower. Found 736pA, maybe better than last time because I tuned quite a bit.

Monday, January 17, 2022, 18:00: Ramping to TGHT 300A, TBHT 230A, where we had sparking problems last time.

Monday, January 17, 2022, 18:17 : So far no sparking issues so I will start to heat up the mass markers. One spark about 4 mins after ramping up, after that maybe 10 sparks/40mins or so. Too many....

Monday, January 17, 2022, 19:20 : Got to 20A on the mass markers, will ramp down now.

Friday, January 28, 2022, 18:49 : Yesterday opened the HV rack to re-start data logging on the thermocouples. This morning ramped everything up and started the heaters. Found the Na current around 250A on the target, but abandoned looking for it because the TGHT heating was causing lots of outgassing, which was causing bias sparks. In addition, there is a weird effect where the Na current spikes, then slowly decreases over the course of an hour or something, to values lower than before the heating. Could this be an indication of some thermal issues, like cold spots where things condense? Or something is drifting. The HV common point on the target is at the mass markers now instead of at the exit of the ion source, but I can't imagine you would see such a large difference. The thermocouples do not change in value during these long slow declines. In light of this, decided to just go up and see what the thermocouples read. Settings were close to what is shown above - bit lower on the HV but magnet the same.

Monday, January 31, 2022, 16:23: Power/sources off. Thermocouple reader off. HV rack open. -AS

Wednesday, February 02, 2022, 07:36: IG1 & Turbo pumps off.  - AS