Due to HV sparking & possible water leaks on the previous TiC & Ta targets, checks are to be performed.

Chamber is empty. U-Line installed. All waterlines purged. FS#2, 3, 4, & 5 are closed.

Vacuum Group LD #2 - Connected to TP1B backing line

Tuesday, August 06, 2024, 15:50: Vacuum @ 3.38e-06T.

Tuesday, August 06, 2024, 15:52: No He connected. 7.0 E-09 atm-cc. LD TP pressure 1.0e-03T.

Tuesday, August 06, 2024, 16:20: No He connected. 1.1 E-08 atm-cc. LD TP pressure 1.0e-03T.

Tuesday, August 06, 2024, 16:23: Open to chamber. 1.6 E-08 atm-cc. LD TP pressure 1.0e-03T. Vacuum @ 2.97e-06T.

Tuesday, August 06, 2024, 16:26: 20 PSI. 1.6 E-08 atm-cc. LD TP pressure 1.0e-03T. Vacuum @ 2.97e-06T.

Tuesday, August 06, 2024, 16:32: FS#5 Charged with 20 PSI He. 1.6 E-08 atm-cc. LD TP pressure 1.0e-03T. Vacuum @ 2.75e-06T.

Tuesday, August 06, 2024, 16:34: Close FS#5

Tuesday, August 06, 2024, 16:35: FS#4 Charged with 20 PSI He. Increase to 2.5 E-08 atm-cc. LD TP pressure 1.0e-03T. Vacuum @ 2.75e-06T.

Tuesday, August 06, 2024, 16:42: While purging FS#4 with HPA, an increase of 8.3 E-08 atm-cc was observed. Vacuum @ 2.75e-06T.

Tuesday, August 06, 2024, 16:50: Re-connected He. FS#3 Charged with 20 PSI He. Increase to from 3.6 to 9.0 E-08 atm-cc. LD TP pressure 1.0e-03T. Vacuum @ 2.59e-06T.

Tuesday, August 06, 2024, 16:52: 5.1 E-08 atm-cc. LD TP pressure 1.0e-03T. Vacuum @ 2.57e-06T. Line still @ 20 PSI.

Tuesday, August 06, 2024, 16:53: Release pressure on FS#3. 5.1 E-08 atm-cc. LD TP pressure 1.0e-03T. Vacuum @ 2.57e-06T. Line still @ 20 PSI.

Tuesday, August 06, 2024, 16:55: FS#2 Charged with 20 PSI He. Steady @ 5.1 E-08 atm-cc. LD TP pressure 1.0e-03T. Vacuum @ 2.59e-06T.

Observed increases on FS#3 & FS4.

Tuesday, August 06, 2024, 17:02: All lines purged with HPA. Allow vacuum to continue down.

Tuesday, August 06, 2024, 17:03: Close off LD to TP1B valve. Dropped to 1.7 E-08 atm-cc. LD TP pressure 1.0e-03T. Vacuum @ 2.48e-06T. Safe to vent LD.

Tuesday, August 06, 2024, 17:06: LD vented & disconnected.

Wednesday, August 07, 2024, 09:15: Vacuum @ 6.43e-07T. Gradually refill the waterlines. 

Wednesday, August 07, 2024, 09:20: FS#5 open. Vacuum remains steady.

Wednesday, August 07, 2024, 09:28: FS#2 open. Vacuum @ 6.38e-07T.

Wednesday, August 07, 2024, 09:30: FS#4 open. Vacuum @ 6.38e-07T. Wait 5 min.

Wednesday, August 07, 2024, 09:35: Vacuum steady @ 6.36e-07T. Occasional dip to 6.27e-07T.

Wednesday, August 07, 2024, 09:36: FS#3 open. Vacuum steady. Wait 5 min.

Wednesday, August 07, 2024, 09:41: No change to vacuum.

While the helium did get through on yesterdays tests as a minor molecular leak, the water does not appear to have an affect. Moving to an empty HV test.

Wednesday, August 07, 2024, 09:53: Vacuum 6.20e-07T.

Wednesday, August 07, 2024, 10:43: Vacuum 6.20e-07T. IG1 & TP off.   -   venting test stand for target installation

Wednesday, August 07, 2024, end of day.  mass marker target installed in test stand with side foil removed so the target is visible through the view port. vacuum roughed, then turbo pumps turned on at end of day for overnight pumping

Thursday, August 08, 2024, 09:19 - vacuum at 6.27e-7T. water cooling was switched on. no effect on vacuum. TGHT and TBHT began ramping at 1A/30s. will test high voltage at low heat and at high heat.

 Thursday, August 08, 2024, 10:04   HV at 35kV. No sparks.  TGHT TBHT at <80A throughout HV ramp and plateau

Thursday, August 08, 2024, 10:14    BIAS down.  TGHT TBHT at 100A. increasing ramp rate to 1.7A/10s. heating up to 480/230

 Thursday, August 08, 2024, 13:59  BIAS has slowly been brought to 28kV . no sparks at all, despite being over 24kV for ~50min. 

Thursday, August 08, 2024, 14:00 increasing TGHT to 580A to attempt to induce sparks. 

Thursday, August 08, 2024, 14:42   at TGHT TBHT 580 230, HV bias at 28kV (with EZL and EE at 0 and 0), no sparks at all over the ramp and over 10 minutes at this condition. 

Thursday, August 08, 2024, 14:43 ramping HV to 30kV

Thursday, August 08, 2024, 15:01  - -  no sparks at 30kV.   bringing up EZL to 13kV  (EE=0)

Thursday, August 08, 2024, 15:11   -  no sparks with EZL at 13kV.  bringing up EE to -2500V

Thursday, August 08, 2024, 15:13  - no sparks with EE at -2500kV

 Thursday, August 08, 2024, 15:22   turned on beam optics to observe beam out, but no beam currently detected on FC0, nor on the wire scanners, nor on FC6. This target commonly has a normal beam output of primarily Na and K

Thursday, August 08, 2024, 15:50  have not been able to deduce reason for lack of beam. increasing BIAS to 50kV.

Thursday, August 08, 2024, 15:51  during ramp up, at 38kV, many optics elements tripped and switched off. however, no spark was registered at the strip tool. not sure of the cause for this.

Thursday, August 08, 2024, 15:54  at 38.8kV, a small spark, only registered on BIAS:RDCUR  (no voltage drop), tripped off beam elements prior to FC0 again.

Thursday, August 08, 2024, 16:00 BIAS at 40kV. no sparks apart from those mentioned immediately above. still have not registered any beam on FC0.

 Thursday, August 08, 2024, 16:02 Vacuum pressure has raised from 6.5e-7 to 1.3e-6 T.

Thursday, August 08, 2024, 16:03  just now, there was a spike drop in pressure and optics elements have shut down again. nothing registered on BIAS, EZL, or EE.

Thursday, August 08, 2024, 16:11   a spark occurred at 43.3 kV

 Thursday, August 08, 2024, 16:23  this spark was audible at the test stand --- ie, not inside

 Thursday, August 08, 2024, 16:51  Saw no indication overall of the same HV sparking issues that we saw with the previous two targets. However, we were unable to generate beam  register any beam output on FC0, FC6, or wire scanners.  And we don't mean 'low signal'. Actually nothing at all.

Thursday, August 08, 2024, 16:54   Ramping down TGHT TBHT now

Friday, August 09, 2024, 08:05   turbo pumps off and spinning down in preparation to vent. will remove the inner foil from the target to observe if a change in shine from the target induces sparking as before. 

Friday, August 09, 2024, 08:58   turbo pumps no longer spinning. venting now.

Friday, August 09, 2024, 10:26    foil stripped off the target. there was a hole in the source for gas (febiad/mass marker). This hole is now plugged. reinstalled, roughing.

Friday, August 09, 2024, 11:59   vacuum at 1.2e-5T.  turning on water cooling lines.  no effect on vacuum.

Friday, August 09, 2024, 12:50 heating TGHT TBHT at 1A/30s

Friday, August 09, 2024, 13:47 increasing heating rate to 1.7A/10s, up to 580/230A

Friday, August 09, 2024, 14:42  TGHT TBHT at 550 230,  increasing BIAS to 30kV 

Friday, August 09, 2024, 15:03   BIAS at 30kV.  no sparks other than a single small one at 25kV. No beam detected at FC0, FC6, or wire scanners.

 Friday, August 09, 2024, 15:18 increased BIAS again. there was one spark at 35kV, then it was stable for 8 minutes with no sparks. still no signal on FC0.  This lack of signal is highly irregular, and should not be the case despite being an empty target. Will have to compare to the next target in the test stand. To attempt to correct, we have:

- manually adjusted gain

- reset bias

- flipped polarity back and forth

- confirmed FC in position

- confirmed no flagged power supply issue

- confirmed clear beam line to FC0

- confirmed upsteam optics are tuned appropriately

Friday, August 09, 2024, 15:23  cooling target and ramping down HV

 Friday, August 09, 2024, 16:06 TGHT TBHT at 0. turbo pumps off and spinning down.

Monday, August 12, 2024, 17:00   EOD. target installed, roughed, turbos on. No effect on vacuum from turning on water cooling lines. TGHT TBHT slowly brought to 230A/230A overnight. 

Tuesday, August 13, 2024, 09:28.  Vacuum at 9.9e-7T.  TGHT TBHT at 210/210. accelerating heating to 230/230. bringing up HV EZL EE to 30 / 2.5 / 13   kV

Tuesday, August 13, 2024, 09:51.  with EZL 13kV, EE 2.5kV. When increasing BIAS from 17.0 to 17.5kV.  Signal becomes detectable on FC0, at 7.75e-10A

Tuesday, August 13, 2024, 10:13  at BIAS 30kV. FC0 and wire scanners appear to be working correctly. FC0 reading 2.66e-8A 

Tuesday, August 13, 2024, 10:13  turning on all beam optics for FC6 mass scan.

 Tuesday, August 13, 2024, 10:31   mass scan procedure is doing a very poor job of recording the background noise. filename  2024-08-13_10-44 Ksalt mm 230-230

Tuesday, August 13, 2024, 10:46   increasing tght to 330

Tuesday, August 13, 2024, 10:59    FC0 at 2.1e-8A

Tuesday, August 13, 2024, 11:12  running mass scan at TGHT TBHT = 330/230 A.   filename 2024-08-13_11-21 Ksalt mm 330-230

Tuesday, August 13, 2024, 11:23 increasing TGHT to 430

Tuesday, August 13, 2024, 11:29  three sparks within 2 min at TGHT 378A.  (no sparks at all previous to this). TGHT ramp aborted. 

Tuesday, August 13, 2024, 11:36  resuming TGHT increase after 6 minutes of no sparks.  

Tuesday, August 13, 2024, 11:51  FC0 reading 1.6e-8.  FC0 signal fluctuating throughout test. rises during ramp and drops during static TGHT TBHT level.

Tuesday, August 13, 2024, 11:53  running mass scan at TGHT TBHT 430/230 A .  filename 2024-08-13_12-16 Ksalt mm 430-230 

Tuesday, August 13, 2024, 12:17  increasing TGHT to 530A.  

Tuesday, August 13, 2024, 12:31  FC0 at 3.03e-8 A

Tuesday, August 13, 2024, 12:31  beginning mass scan   -  filename   2024-08-13_13-02 Ksalt mm 530-230

Tuesday, August 13, 2024, 13:02 increasing TGHT to 580A 

Tuesday, August 13, 2024, 13:13   FC0 at 3.58e-8A.  beginning mass scan - filename  2024-08-13_13-35 Ksalt mm 580-230

Tuesday, August 13, 2024, 13:37    increasing bias to test sparking

Tuesday, August 13, 2024, 13:58   at 37kV, a number of optics elements prior to FC0 went down. no voltage or current spikes

Tuesday, August 13, 2024, 13:59  at 42.4kV, a couple sparks, seem to involve TGHT and BIAS. these dropped a few optics elements. when I brought them back up, they went down again, at a time with no voltage or current spikes.

Tuesday, August 13, 2024, 14:30 at 43.6kV, the sparking frequency became regular, with HV bias sparks occurring approximately every 5 minutes

Tuesday, August 13, 2024, 17:00 considerable time was spent until end of day manipulating the bias and the TGHT current level in an effort to discover the location of the regular sparking

increases in HV were found to increase the frequency of sparking, and eventually the HV increase was found to hit a threshold where the current would increase noticeably, with a stable voltage. this was accompanied by a buzzing coming from the feedthroughs on top of the cage. seemed to be coming from the TGHT(+) feedthrough. At no time did there appear to be sparking within the chamber of the test stand. In one instance, with HV just below the threshold of buzzing, increasing TGHT seemed to induce the buzzing state.

Wednesday, August 14, 2024, 11:16  ramping up bias to HV. intending to push HV today to find the source of these sparks and buzzing. initially, will be observing this with TGHT TBHT at 180/180 A

Wednesday, August 14, 2024, 11:47 at BIAS = 32.6kV (with EE 2.5 kV and EZL 13 kV), HV appears to be stable. Yesterday, we observed a fluctuating BIAS current which seemed to culminate in regular sparking activity (although this was at voltages of >40kV)

 Wednesday, August 14, 2024, 12:26 at bias = 38.8kV, there was a significant accompanying increase in BIAS current, but no evidence of sparking or buzzing

 Wednesday, August 14, 2024, 12:46  at BIAS = 49.2kV, the buzzing begins.  On the strip tool this is also seen as a large jump in current, with stable voltage

Wednesday, August 14, 2024, 12:49  dropping the bias by ~1kV stopped the buzzing. ramping up quickly again caused a spark and more buzzing.  increasing the voltage to attempt to locate the source.

Wednesday, August 14, 2024, 13:18   at bias of 49.2kV, buzzing began. dropping the bias stopped it. to attempt to locate the source, we increased the bias significantly. At 53kV, the bias power supply began to current limit. when this was increased, a spark caused the putty connection at the test stand to disconnect and two turbo pumps to trip off. once restored, another increase of the bias eventually caused a large spark when trying to locate the buzzing sound. Again, it seems to be at the feedthroughs of TGHT TBHT. My guess is TGHT+, but there is nothing visual to confirm it is coming from there. This buzzing state is also accompanied by a drop in EZL current to 0 and a large increase in EZL voltage readback.

 Wednesday, August 14, 2024, 15:05 dropped the HV and removed the cage to investigate any issues. we propose that this likely involves jumping to the einzel lens and are curious if raising the EZL voltage significantly would prevent this state from recurring. cage back on, raising HV

Resuming testing after TGHT TBHT power supply updates:

Friday, September 06, 2024, 12:09:   Ramped up TGHT and TBHT to ~170A at 1A/30s.  Increasing ramp rate to 1.7A/10s up to 580A/230A

 Friday, September 06, 2024, 14:11  slowly increasing BIAS, EE and EZL to 30kV, 2.5kV, 13kV

Friday, September 06, 2024, 15:53  appears that FC0 and wire scanners are working normally. However, there is a threshold reading problem with FC6. seems that a negative readout is present on FC6 if there is no substantial signal, and then nothing is recorded to the mass scans.

Friday, September 06, 2024, 15:54  increasing voltage to test high voltage sparking (BIAS AND EZL)

Friday, September 06, 2024, 16:23  after resetting the FC6 polarity and the FC6 bias, the background signal began showing up.

Tuesday, September 10, 2024, 12:19  Test stand vented, target removed.

Friday, September 06, 2024:  New TSH:TGHT power supply has been installed and is now functional. Magna-Power TSD-900/208. The TSH:TBHT power supply has also been cleaned, and the COIL power supply replaced with a duplicate that should function identically.

 Monday, October 07, 2024, 09:54: Roughing. U-Line installed on HS waterline.

Monday, October 07, 2024, 10:34: Vent Chamber. TP6 & TP2 off.

Wednesday, October 09, 2024, 11:28   Target loaded, remote power supply added for mass marker, negative channel on pin 5, positive channel on pin 7.

Wednesday, October 09, 2024, 11:50   roughing

 Wednesday, October 09, 2024, 12:51   Turbo pumps TP1A TP1B on

 Thursday, October 10, 2024, 09:27:   Water cooling turned on. no effect on vacuum (2.6e-6T)

Thursday, October 10, 2024, 09:45:   Increasing TGHT TBHT to 150/150A at 1A/30s

Thursday, October 10, 2024, 11:07    TGHT TBHT at 120/120A  .   increasing TGHT TBHT to 580/230 at 1A/10s 

Thursday, October 10, 2024, 12:29   during the current increase, when TBHT was at 230 and TGHT reached ~460, the TBHT current began decreasing. Upon inspection, the TBHT voltage is higher than normal and hitting its limit. It may be that there is another current path. that is, it may be shorted. 

as TGHT increases, TBHT voltage continues to increase.   TGHT voltage is similarly higher than usual, at 6V to deliver 500A.

on another note, the vacuum value has been increasing slowly throughout heating, possibly due to the presence of indium within the mass marker reservoir, or simply because this target has not been hot for some time. Leaving TGHT at 502A for the time being.

Thursday, October 10, 2024, 13:34    Increasing BIAS/EE/EZL to 30/2.5/13 kV. 

Thursday, October 10, 2024, 14:27  beginning mass scan - reservoir at 0 A. (reservoir contains solid Indium)    - mass scan res In 0A

 Thursday, October 10, 2024, 15:19   increased current through reservoir with magnet sitting at mass 115 - noticeable increase in Indium presence in beam beginning at ~2.5A. Brought res current to 3.0A, waited for FC6 current to plateau.- at 5e-10A

Thursday, October 10, 2024, 15:27   mass scan run again

Thursday, October 10, 2024, 15:57   res current decreased to 0A

Thursday, October 10, 2024, 15:57  dropping voltages to 0V 

Thursday, October 10, 2024, 16:12  voltages at 0, decreasing TGHT TBHT at 1A/30s 

 Thursday, October 31, 2024, 13:53: Roughing down empty chamber. U-Line installed.

Monday, November 04, 2024, 11:40: Vent beamline. 

Monday, November 04, 2024, 13:40: 1/2 operating filament spare provided & installed. Roughing beamline section.

Monday, November 04, 2024, 13:51: TMS:TP2 on. 

Monday, November 04, 2024, 13:57: TMS:TP6 on. TMS:IG6 on.

Tuesday, November 05, 2024, 15:00: Venting Chamber

Tuesday, November 05, 2024, 15:19: IG6 still displaying issues. Contacted Edi, 

Tuesday, November 05, 2024, 15:35: Controller replaced. Switch to Filament 2. IG6 on. Reading 3.73e-07T. 

Wednesday, November 13, 2024, 09:16: IG6 is tripped again. 

Wednesday, November 13, 2024, 09:17: Reset & switched back to Filament 2. There is no filament 1. Reading 3.91e-07T.

42972-5 Base / 42972-9 Lid

Tuesday, November 05, 2024, 16:30: Roughing. 

Tuesday, November 05, 2024, 17:04: TP1B on.

Tuesday, November 05, 2024, 17:13: TP1A on.

Tuesday, November 05, 2024, 17:21: IG1 on @ 2.41e-05T 

Wednesday, November 06, 2024, 10:35: Vacuum @ 5.75e-07T. Waterline FS#5 open. 

Wednesday, November 06, 2024, 16:24: TGHT/TBHT ramping to 580/230A at 2A/min

Thursday, November 07, 2024, 09:16:  Increasing BIAS/EE/EZL to 30/2.5/13 kV slowly

Thursday, November 07, 2024, 11:26:  as expected, no beam out to FC0. slowly increasing to bias to 45kV alongside ezl to 28kV

Thursday, November 07, 2024, 11:27:   TGHT dropped out for 1s. Did not register a trip or anything. simply jumped down to 0A and immediately recovered.

Thursday, November 07, 2024, 14:40:   At 45kV, there were no sparks noticed. The target assembly was brought down to 0V and ramped down to 0A/0A at -2A/min  

Wednesday, November 13, 2024, 09:15: PS Off. TP off - AS. 

Wednesday, November 13, 2024, 11:26: VV1 opened - BB. 

 Tuesday, November 19, 2024, 14:25: Roughing

Opened the ATTS, placed what I will call “Cast Alumina Sample #1” into the ATTS and activated the roughing then turbo pumps. Currently sample is in slow heating progress to 1000 degrees Celsius, process is expected to take some time, so I'll revisit after lunch.

 November 28, 2024 1:46PM

Checked in on sample in ATTS.

Tuesday, December 03, 2024, 14:55  ANODE/CATHODE power supply switched to cathode mode, NEGATIVE

  Tuesday, December 03, 2024, 15:48

Switched out pellets in ATTS, brought pressures down to ~10 uTorr, heated and cooled sample.

  Wednesday, December 04, 2024, 15:42 Depressurized the ATTS

 Thursday, December 05, 2024, 11:04: RP1 was struggling to pump down. RP SN: MY20055A02 removed. Tip seal replacement likely req'd.

Swapped with a new roughing pump SN: MY2340SA06 (Voltage set to 115V. Shipping locks loosened prior to install)

Ballast filter installed.

Thursday, December 05, 2024, 11:05: Roughing.

Thursday, December 05, 2024, 11:10: Vacuum pressure dropping optimally. Down below 1T already

Thursday, December 05, 2024, 11:47: TP & other RP ok. Note TP1A is getting louder on startup. Will likely need a change out in Q1 - 2025.

Additional source tray inspection:

Monday, December 16, 2024, 15:30: OK

Images attached.

 Thursday, December 05, 2024, 14:05 Pressurized ATTS with argon, swapped out samples, and repressurized and heated chamber.

Tuesday, December 02, 2024, 15:35    - Target loaded into the test stand

Thursday, December 03, 2024, 14:33 - as per elog entry 1033, test stand has been changed to CATHODE mode, and wiring within the Faraday cage has been altered appropriately. Additionally, a GeMov resistor has been added to potentially reduce the sparking problems that have previously tripped the TGHT power supply

Thursday, December 04, 2024, 10:00    - Roughing pump having trouble reaching suitable vacuum - possible replacement required.

Thursday, December 05, 2024, 13:37  - Turbo pumps on

Wednesday, December 11, 2024, 15:02   dropped bias/ee/ezl to 0

Wednesday, December 11, 2024, 15:02    Must cool target to investigate Cathode short. Prior to installation, target isolation was confirmed. If the cathode dropped to contact the copper plate shielding the coil, this would be evidence to support keeping the retainer.

Thursday, December 12, 2024, 09:24   after cooling, cathode power supply was checked to see if shorted and it is indeed still shorted out.

 Thursday, December 12, 2024, 09:25   turning off turbo pumps to spin down 

Thursday, December 12, 2024, 11:30:     venting chamber  

 Friday December 13:   after venting the chamber and removing the target. The target appears to be unshorted and intact. However, upon inspection of the test stand, there appears to be a ~100Ω load between the cathode and ground. This load is able to sustain voltage from the cathode power supply, but draws a significant amount of current. It is too much for operation, and might be further aggravated by the presence of the target. Further, when the TGHT and TBHT terminals are shorted together, the resistance from cathode to ground drops to ~1Ω. Perhaps this could be associated with the installation of the TGHT power supply, as FEBIAD has not been run on this machine since it was installed.   Wiring at the feedthroughs as been quadruple checked, I don't believe that the problem lies there.

With no target in place, the cathode was able to hold a voltage, despite drawing 100+mA current. However, I was unable to repeat further tests, as the power supply stopped responding. Despite ramping up to ~10V in epics, the readback is 0V/0A, unlike before.

  Friday, December 06, 2024, 16:03 Heated and cooled a sample in the ATTS 3x

  Tuesday, December 10, 2024, 14:38 Depressurized ATTS using argon, switched out samples, and repressurized ATTS. Heated new sample to 1000 degrees Celsius.

Monday, December 16, 2024, 3:34   Target loaded in test stand. Confirmed correct connection to mass marker power supply through multipin. Bottom left pin (5 PS - ) connected to grounded side of the filament, top right pin (2, PS +) connected to top end of filament.

Tuesday, December 17, 2024, 09:30 Turbo pumps on

Tuesday, December 17, 2024, 16:21  water cooling on. No effect on vacuum. Vacuum stable at 1.18e-6T

Tuesday, December 17, 2024, 16:41   ramping TGHT TBHT at 1A/30s

Wednesday, December 18, 2024, 10:00  slowly increasing BIAS/EE/EZL to 30/2.5/13 kV

Wednesday, December 18, 2024, 11:40   BIAS EE EZL at 30 2.5 13 kV. 1 spark at 28kV, and there was a downward spike in the TGHT current when bias was at 28.5 kV  

Wednesday, December 18, 2024, 11:41   FC0 reading 1.6E-10 A. quite low for total beam, but this is likely due to this target being hot so many times.

Wednesday, December 18, 2024, 11:51 wire scans taken (RPM0)

Wednesday, December 18, 2024, 11:54 FC) extracted for mass scan - mass scan beginning now . Background record appears to be functioning well, although it is high. comparatively to old tests. It could be that those old tests were recording irregularly low background, given the temporary solution that was implemented.

Wednesday, December 18, 2024, 12:13   it seems that a spark took down many optics elements. Going to allow conditioning at 30kV for a while before restarting .     - optics elements down due to pressure sensor TMS:IG6 timing out. Vacuum group notified. Will likely bypass the interlock temporarily if it cannot be fixed fast. This should get a more permanent solution as it has failed a number of times before.

 Wednesday, December 18, 2024, 13:06    sparks are occurring on average approximately once every 10 minutes. they don't seem to be tripping of any supplies or optics (after IG6). but this spark frequency is significantly higher than observed on other targets lately.

Wednesday, December 18, 2024, 13:24   restarting Mass scan with IG6 interlock forced by.   scan name - 2024-12-18_13-47 SISP2N mmOFF.txt

Wednesday, December 18, 2024, 13:51   put FC0 back in, preparing to heat up mass marker.  will plan to ramp to 3A to match previous MM tests.     also, no sparks in the past 40 minutes, it appears they have subsided.    additionally, IG6 has been fixed by vacuum group

 Wednesday, December 18, 2024, 14:15   mass marker power supply is not connecting. When attempting to write to its IP address it times out. Had to drop the HV in order to investigate. Have enlisted controls group to aid as it appears to be connected and should be functional.  

Wednesday, December 18, 2024, 14:30   had to reset the computer connection to the network 192.168.5. by unplugging and plugging in the usb ethernet connection at computer. situation resolved.

Wednesday, December 18, 2024, 14:40   HV back up and now increasing the mass marker current from 0A to 3A, at 0A, FC0 current is 1.4e-10, very close to previously recorded FC0 mm0A value.

Wednesday, December 18, 2024, 14:56 with mm current at 3.0A, requiring 6V, FC0 current is 2.1e-10 A.   

Wednesday, December 18, 2024, 14:58  withdrawing FC0 to take mass scan

Wednesday, December 18, 2024, 15:25   mass scan complete:  filename 2024-12-18 15-23 SISP2N mmON.txt

Wednesday, December 18, 2024, 15:27   further increasing mm current to 4.0A.  FC0 current increasing noticeably. waiting for plateau. FC0 at 6.6e-10A.   wire scans taken

Wednesday, December 18, 2024, 15:39  new mass scan:  2024-12-18 15-53 SISP2N mmON 4A.txt

Wednesday, December 18, 2024, 15:52  mm power supply turned off. 0A.

Wednesday, December 18, 2024, 15:53  rescan of high mass region. still a residual indium mass peak present. will scan again after cooling more.

Wednesday, December 18, 2024, 16:10   mass scan captured that shows the indium peak almost masked in background 

Given that the indium peak for 3A was significantly lower than with a regular SIS source cup, i recommend that this target is heated up with the regular source cup again to compare.

 Wednesday, December 18, 2024, 16:11 dropping HV EE EZL to 0V

Wednesday, December 18, 2024, 16:13 cooling target to 0/0A at 1A/30s

 Note, ground and HVC (high voltage common) are used interchangeably here.

Monday, December 16, 2024,   in the previous test, elog 1038, it was found that the cathode was unable to hold any voltage and was shorted to HVC. The cathode was shorted directly to ground, with the cathode supply current limiting upon being powered, unable to reach even 1V.

After testing, the ANODE power supply stopped functioning and was unable to provide and voltage or current.

When the target was removed, it was found that the TBHT terminal was just ~100Ω from HVC. When I shorted the TGHT to TBHT terminal, as they are when the target is installed, the resistance from TBHT to HVC dropped to just 1Ω. Prior to the anode power supply stopping, it was found that when it was powered on with no target present, it was able to hold voltage, but still drew significant current: up to 400mA when provided less that 20V. This should be completely open, losing no current at all.

Keiko and the controls team have been looped in to address the issue with the ANODE power supply as it may be a controls issue. They believe there are a few possibilities for its error that must be investigated prior to deferring to the power supplies group. This will continue to be investigated

    ********** UPDATE: ISSUE RESOLVED ********* There is simply a physically triggered interlock that requires the faraday cage door to be closed to operate the ANODE power supply

When investigating the resistive short from the TBHT, I first noted the resistances between each of the channels: TGHT(-) to TGHT(+) 30↨Ω; TBHT(-) to TBHT(+) 20Ω; TBHT(-) to TGHT(-) 100Ω; TBHT(+) to TGHT(+) 140Ω. I also reconfirmed and noted relevant connections at the feedthroughs: There are NO visible shorts to HVC from the TGHT or TBHT feedthroughs. From TGHT(-), there is one 50kΩ resistor with varistor, between TGHT(-) and TGHT(+) there is a100Ω with varistor. I then removed the back of the faraday cage to investigate possible paths to ground from the TGHT and/or TBHT. This showed that TGHT- was grounded through a varistor (checked, functioning correctly, OL at low voltage), TGHT- to + has varistor||100Ω, TBHT- to + has varistor||100Ω, and TBHT- to TGHT- has varistor||100Ω. These fit in accordance with the observed resistances between the terminals.  

I also disconnected the ANODE power supply from its output wire to further investigate without possible issues from the power supply. At this point, (after I had remade the varistor connections) I began to observe that the TGHT and TBHT terminals were all detached from ground by 50kΩ (expected amount, given that there is a 100k||100k resistor from TBHT- feedthrough to ground). When I reattached the anode power supply, that value dropped to 35kΩ, I assume due to internal resistance of the power supply. I placed everything back in position and (repeatedly) ensured that the 35kΩ separation persisted. It seems that this shorting issue has resolved itself. It may be that the was an accidental connection made from an unshielded wire inside the faraday cage.