Aggregator

Log Number: 4471780Logbook(s): 

• ELOG

Entry Makers: dchriBody: 

Log Number: 4471779Logbook(s): 

• ELOG

Tags: 

• Autolog

Body: High Voltage was turned off for:
R02
R03
R04
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: 4471778Logbook(s): 

• ELOG

Tags: 

• Autolog

Body: High Voltage was turned off for:
R22
R23
R24
R25
R26
R27
R28
R29
R2A
R2B
R2C
R2D
R2E
R2F
R2G
R2H
R2I
R2J
R2K
R2L
R2M
R2N
R2O
R2P
R2Q

Log Number: 4471776Logbook(s): 

• ELOG

Tags: 

• Autolog

Body: Destination Masking to: Inj500KeV
User: dchri

Log Number: 4471774Logbook(s): 

• POLOG
• ELOG

Body: 

- Had visitors from KEK and BNL.

Log Number: 4471773Logbook(s): 

• ELOG

Body: 

With JT valve & Cryo Heater Parameters set to those found in this procedure...
JT seemed to settle between 75% and 82%
JT with all RF cavities on settled between 78% and 80%

Cavity 5 stood out the most to me
Turn cav 5 off --> JT reduced ~ 2 to 4 % from all cavities on baseline
Turn cav 5 on --> JT increased ~2 to 4% from all cavities on baseline

More details with plot images & timestamps
https://logbooks.jlab.org/entry/4471763

With a HIGH baseline heat (200W), JT settles at a high setpoint, and thus takes less steps when maintaining helium.
The JT already has +/- ~ 1% movement with no chan

Log Number: 4471771Logbook(s): 

• ELOG

Body: 

Only remaining area is 2L26 girders LCW valves. These will be done once their magnets are re-assembled and LCW hook up completed.

Log Number: 4471770Logbook(s): 

• ELOG

Body: 

HCO of 1S LCW valves and magnets performed, all good, HCO updated. Also did LCW valves shut for 2L03 swap. All associated valves open.

Log Number: 4471769Logbook(s): 

• POLOG
• ELOG

Body: Spot Location: (13250,19250), Charge: 1.998958

Laser Wavelength Atten Setting Laser Power Current HV PS Current QE PV Updated? Update Time/Reason Not Updated (nm) (W) (uA) </

Log Number: 4471768Logbook(s): 

• ELOG

Body: 

All leaks fixed, magnet re-installed

Log Number: 4471767Logbook(s): 

• ELOG

Body: 

Flow checks performed and passed IR check.

Log Number: 4471765Logbook(s): 

• ELOG
• RFLOG

Entry Makers: kpriceBody: 

GASK was high enough to cause SOSing. Tried open-loop tuning but ultimately had to open up the attenuator considerably (9.3 -> 2) to get GASK into a reasonable range. This cavity is really touchy when it comes to tuner movement - no change for a long time, then huge swings with very few steps.

Log Number: 4471763Logbook(s): 

• SRFLOG
• CLOG
• ELOG

Entry Makers: dchriBody: 

ATLis https://tasklists.jlab.org/atlis/tasks/119484

Investigating the high heat load in 1L06

Initial JT parameters:
Sample Time = 120
Max Position = 85

Initial Heater parameters:
Requested Heat Watts = 165
LEM Requested RF Heat = 100

STEPS:
1. Reduce ST (JT sample time) to 30s
2. Raise Max Pos to 90%
3. Raise heater 'REQ HEAT WATTS' to 200W
4.

Log Number: 4471762Logbook(s): 

• ELOG

Entry Makers: dchriBody: 

Cavity had trouble coming up. OLT and letting it rest at 11.5 MV/m (drive high 12 MV/m)

Log Number: 4471761Logbook(s): 

• SRFLOG
• ELOG
• RFLOG

Entry Makers: dchriBody: 

Spikes in VIP1L0640 while bringing up cavity 5

Initially, Forward power was way too high. open loop tune, walked cavity up...

Going to let it sit at 7.5 MV/m

Anything above that causes a Vac fault

Log Number: 4471760Logbook(s): 

• ELOG
• LERFLOG

Body:  ACCELERATOR OPERATOR SIGN IN FORM OPERATOR:    Christian
DATE:             02/17/2026
SHIFT:               Owl

The operator has read the following:

• ELOG
• PD Shift Plan
• Radiation Surveys for PSS Segments in Controlled Access
• PSS Log

Log Number: 4471759Logbook(s): 

• ELOG

Tags: 

• Autolog

Body: saver ran from opsl632

Saved: kprice 02-18-26 00:14:45 {A:5 B:3 C:1 E:345 A=BS B=BS C=BS D=BS 0R08=0.00 0R08 dump in.

Log Number: 4471758Logbook(s): 

• ELOG

Body: 

Subcontractor is tentatively scheduled to loaded revised Central Chiller System software on Thursday 2-19-26 which will require Building 60 chillers, primary pumps, secondary pumps, cooling tower pumps, and cooling tower fans to be switched to manual operation. The existing remote differential pressure sensor located at Test Lab TLA Air Handling Unit 58-AHU-2 will need to be replaced and revised control software loaded. Loading the revised control software will require a brief shutdown of 58-AHU-2 which conditions the TLA R&D Chem Room.

Log Number: 4471757Logbook(s): 

• ELOG
• LERFLOG

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

Date : 02-17-26
Time : 23:15:06
Day : Tuesday
Shift : Owl

Crew Chief : Price
Program Deputy: Buttles
Team : D
Designated SSO: Christian
LERF Operator:
Operators : Christian

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

Log Number: 4471756Logbook(s): 

• ELOG
• RFLOG

Tags: 

• Autolog

Body: 

The following cavities have been GSET 0:
2L14-6
Username: bschauml
Date/Time: 02-17-26_22:36:27
RF Status: Bad
Tuner Status: Good
Comment: GSET 0 - stepped off +100k - No CRFP Readback - ELOG 4471755
Special Instructions:

Maintenance Tag: Component: Operator Entry - See SME