Aggregator

Log Number: 4475294Logbook(s): 

• ELOG

Tags: 

• Autolog

Body: High Voltage was turned off for:
R12
R13
R14
R15
R16
R17
R18
R19
R1A
R1B
R1C
R1D
R1E
R1F
R1G
R1H
R1I
R1J
R1K
R1L
R1M
R1N
R1O
R1P
R1Q

Log Number: 4475293Logbook(s): 

• ELOG
• LERFLOG

Body: 
THOMAS JEFFERSON NATIONAL ACCELERATOR FACILITY
ACCELERATOR OPERATIONS CREW CHIEF SIGN IN FORM

Date : 03-10-26
Time : 07:11:13
Day : Tuesday
Shift : Day

Crew Chief : Mock
Program Deputy: Schoene
Team : B
Arm : Barker
Designated SSO: Thomas
LERF Operator:
Operators : Barker, Thomas

This stamp certifies that the above Crew Chief has read/reviewed/received the following:

Log Number: 4475291Logbook(s): 

• ELOG

Tags: 

• Autolog

Body: 

The following box supplies were TURNED OFF by version 2-16 of the Box Supply Cycling Script:
ARC1A Ramp Rate = 6.964 A/s
ARC2A Ramp Rate = 6.712 A/s
ARC3A Ramp Rate = 9.294 A/s
ARC4A Ramp Rate = 9.299 A/s
ARC5A Ramp Rate = 9.307 A/s
ARC6A Ramp Rate = 8.835 A/s
ARC8A Ramp Rate = 10.637 A/s
ARC9A Ramp Rate = 9.322 A/s
ARCAA Ramp Rate = 10.852 A/s
DOG1E Ramp Rate = 2.750 A/s
DOG2E Ramp Rate N/A
DOG3E Ramp Rate N/A
DOG4E Ramp Rate N/A
DOG5E Ramp Rate N/A
DOG6E Ramp Rate N/A
DOG7E Ramp Rate N/A
DOG8E Ramp Rate N/A
DOG9E Ramp Rate N/A
RSEP8A Ramp Rate = 10.104 A/s
RSEP9A

Log Number: 4475290Logbook(s): 

• POLOG
• ELOG

Body: 

- Reconfigured injector for 140 kV Gun HV.
- Activated photocathode.
- Started beam restoration to 1D.

Log Number: 4475289Logbook(s): 

• POLOG
• ELOG

Entry Makers: samariBody: 

I loaded the values for the prebuncher and buncher from the 2024 all save (pb=3.55, b=4.3 gset), and phased accordingly.

Fig 1: Prebuncher + buncher off
Fig 2: Prebuncher on
Fig 3: Buncher+prebuncher on

Log Number: 4475288Logbook(s): 

• POLOG
• ELOG

Entry Makers: samariBody: 

Loaded All save from previously known 140 KeV set up (wiens off), then threaded beam through to the 1D with all warm RF off. I had to make a few solenoid changes to get good enough beam for transport. I roughly centered through all lenses up to 1D. Attached is the viewer walk and the differences from the all save.

Log Number: 4475285Logbook(s): 

• ELOG

Tags: 

• Autolog

Body: saver ran from opsl632
Data from: /usr/opdata/burt/allsnap/05-09-24_15:52:54
Restored file: /tmp/03-10-26_05:02:34.snap


Downloading 2024 run all save

Log Number: 4475284Logbook(s): 

• ELOG

Entry Makers: deirBody: 

Reset masking to Injector 500keV.

Opened up VBV0I06 to clear FSD. Closed the valves around the booster. The 0I06 valve was closed as a precaution to protect the booster. Since we are back to being limited to Mode 0, the booster RF cannot be turned on so there is no issue with keeping those valves closed.

Log Number: 4475283Logbook(s): 

• ELOG

Tags: 

• Autolog

Body: saver ran from opsl632

Saved: samari 03-10-26 05:02:15 {A:i B:5 C:2 E:345 A=BS B=BS C=BS D=BS 0R08=0.00 0R08 dump in. Autosave prior to restore.

Log Number: 4475282Logbook(s): 

• POLOG
• ELOG

Entry Makers: samariBody: 

At the request of CIS, I'll begin threading viewer limited beam to 1D. First, I'll load all save #25231 from the 2024 as mentioned in the linked log.

Log Number: 4475281Logbook(s): 

• ELOG

Entry Makers: deirBody: 

Gun is on at 140 kV and CIS has given permission to run viewer limited beam only.

Log Number: 4475280Logbook(s): 

• ELOG

Tags: 

• Autolog

Body: Destination Masking to: Inj500KeV
User: deir

Log Number: 4475279Logbook(s): 

• POLOG
• ELOG

Entry Makers: msmithBody: 

Moved the MBO0I06 slider until the INJ dropped to power permit, as expected

Log Number: 4475278Logbook(s): 

• POLOG
• ELOG

Body: 

QE Scan (max QE = 1.26%):
https://logbooks.jlab.org/entry/4475275

Log Number: 4475276Logbook(s): 

• POLOG
• ELOG

Entry Makers: suleimanBody: 

Vacuum is Ok to open valves.

Log Number: 4475272Logbook(s): 

• POLOG
• ELOG

Body: 

The SLSP-5247-4 GaAs photocathode mounted on puck #3 has been activated with 15 yo-yo's (5 mm mask). The puck has been inserted in the gun with the ear at about 15 degrees CCW from the vertical direction (same angle as before). At the long manipulator, this corresponds to 25 degrees.

The HV bias was set to "5" on the battery box. The picoammeter was set 200 nA Full Scale then 2 uA after the second yo-yo.

The Cs was heated with 4.6 A (0.98 V) and vacuum went to 9 nA. The first QE Cs peak started to show up after 14 minutes.

Log Number: 4475271Logbook(s): 

• ELOG

Entry Makers: samariBody: 

Fig one shows its been steadily rising since early February, but now its averaging at 85 and spiking to 100 (fig 2)

Log Number: 4475270Logbook(s): 

• ELOG
• POLOG

Body: 

Heated puck # 3 in oven and soaked between 500 and 509 C for 30 minutes. Heater at 8.7 Amp and 3.95 V. Vacuum went from 0.4 nA to 72 nA. When stopped soaking, degassed Cs source at 4.7 A for 10 seconds; vacuum went from to 42 nA to 100 nA.

Log Number: 4475269Logbook(s): 

• ELOG

Entry Makers: samariBody: 

17 hours ago at around 8:05, the exit stair 4 dehumidifier was turned off to verify that it was the cause of the detuning. We see that when it is turned off it has a massive effect. While it was on, we saw many cavities frequently hitting their step limit of 50k (middle graph in Fig 1). Afterwards, the cavities are tuning regularly and have consistent forward power (fig 2).

It would be really helpful to do this same exercise with the exit stair 1 dehumidifier, as we see the exact same issue happening in zones 1L16:1L21.

Log Number: 4475268Logbook(s): 

• ELOG
• RFLOG

Tags: 

• Autolog

Body: 

The following cavity histories have been updated:
2L08-3
Username: samari
Date/Time: 03-10-26_00:17:32
RF Status: Good
Tuner Status: Good
Comment: RF Recovered, see log 4475130
Special Instructions:

Maintenance Tag: Component: Operator Entry - See SME