Aggregator

Log Number: 4474930Logbook(s): 

• ELOG

Entry Makers: deirBody: 

Fig 1: Cavity 1 - No significant change from 8 MV/m -> 9.5 MV/m

Fig 2: Cavity 2 - Roughly 1R/hr increase in C100 neutron rates going from 10 MV/m to 13 MV/m. An additional 3 R/hr going from 13.0 to 14.8 MV/m. This large increase in neutron dose rate seems to start at 14.0 MV/m.

Log Number: 4474929Logbook(s): 

• ELOG

Entry Makers: samariBody: 

The cavity started SOSing so I walked gradient down and was going to see if it wasn't tuned well. With a GLOD of -1.1 I could only get 0.06 kW of CRFP, and tuning showed we were on resonance. The attenuator is already at 0 dB. GASK has been rising for the past couple days.

Log Number: 4474928Logbook(s): 

• ELOG

Entry Makers: msmithBody: 

Cavity started SOSing. OLT'd and zeroed the detune angle

Log Number: 4474927Logbook(s): 

• ELOG

Entry Makers: samariBody: 

On the 5th around noon the readback went to zero, but no impact on LO or IF in the zone or others downstream of it. No mention of any work on the zone in the logs, and zone was off at the time.

Log Number: 4474926Logbook(s): 

• ELOG
• RFLOG

Tags: 

• Autolog

Body: 

The following cavity histories have been updated:
1L23-8
Username: deir
Date/Time: 03-07-26_00:44:07
RF Status: Bad
Tuner Status: Good
Comment: C100 Bypassed - KCCU High faults dropping zone https://logbooks.jlab.org/entry/4474925
Special Instructions:

Maintenance Tag: Component: Operator Entry - See SME

Log Number: 4474925Logbook(s): 

• ELOG

Entry Makers: deirBody: 

Very noisy KCCU and KFVM signals.

Filament board was replaced recently. Bypassing for now to keep the zone on.

Log Number: 4474924Logbook(s): 

• ELOG
• LERFLOG

Body:  ACCELERATOR OPERATOR SIGN IN FORM OPERATOR:    Smith
DATE:             03/06/2026
SHIFT:               Owl

The operator has read the following:

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

Log Number: 4474923Logbook(s): 

• ELOG
• LERFLOG

Body:  ACCELERATOR OPERATOR SIGN IN FORM OPERATOR:    Samari
DATE:             03/07/2026
SHIFT:               Owl

The operator has read the following:

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

Log Number: 4474922Logbook(s): 

• ELOG
• RFLOG

Tags: 

• Autolog

Body: 

The following cavities have been GSET 0:
1L02-6
Username: deir
Date/Time: 03-06-26_23:17:08
RF Status: Bad
Tuner Status: Good
Comment: GSET 0 - stepped off +100k - RF set to bad by SME. Taking it out of operation.
Special Instructions:

Maintenance Tag: Component: Operator Entry - See SME

Log Number: 4474921Logbook(s): 

• ELOG
• LERFLOG

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

Date : 03-06-26
Time : 23:11:36
Day : Friday
Shift : Owl

Crew Chief : Deir
Program Deputy: Schoene
Team : A
Arm : Smith
Designated SSO: Samari
LERF Operator:
Operators : Samari, Smith

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

Log Number: 4474920Logbook(s): 

• ELOG
• SLOG

Tags: 

• MCC8am
• Software and Controls

Body: 

Implementation of the new pockel cell HV driver alarms
IOC HCO to Hall B, C, D
Global Channel Access Security Closed

Log Number: 4474917Logbook(s): 

• ELOG

Entry Makers: bschaumlBody: 

I am unsure if this is real or just a blip in the PV, but no systems appear to have been unsettled by the dip.

Log Number: 4474916Logbook(s): 

• ELOG
• LERFLOG

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

Date : 03-06-26
Time : 18:57:10
Day : Friday
Shift : Swing

Crew Chief : Richardson
Program Deputy: Schoene
Team : X
Arm : RADCON
Designated SSO: Schaumloffel
LERF Operator:
Operators : Schaumloffel, Yoon

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

Log Number: 4474886Logbook(s): 

• ELOG

Body: 

More troubleshooting at 2L03 required. Removed Klystron jumpers and still had DC overcurrent trips. Some component in the CPS could be causing the overcurrent. Checked DC overcurrent circuit and it's working properly. Checked diode stack, but no clear sign of malfunction there.

Log Number: 4474885Logbook(s): 

• ELOG

Tags: 

• Autolog
• MCC8am

Body:  */ ATLis Comments Posted 18:00 Thursday March 05 through 18:00 Friday March 06 AES DC power Systems Investigate and Troubleshoot YBBS06 ARC7 Shunt failure

2026-03-06 13:03 - Kevin O'Brien

Log Number: 4474875Logbook(s): 

• POLOG
• ELOG

Body: 

No leaks detected after cleaning. Group will meet tomorrow AM to install a new HV cable and determine the best way to ramp up the gun (hipot) with no beam anticipated tomorrow.

Log Number: 4474873Logbook(s): 

• ELOG
• LERFLOG

Body:  ACCELERATOR OPERATOR SIGN IN FORM OPERATOR:    Schaumloffel
DATE:             03/06/2026
SHIFT:               Swing

The operator has read the following:

Log Number: 4474870Logbook(s): 

• ELOG

Body: 

Task moved to maintenance day on Weds 3/11 at 9am

Log Number: 4474868Logbook(s): 

• POLOG
• ELOG

Body: 

Helium leak check gun ceramic insulator once silicone grease removed. No leak detectable using the RGA on the prep chamber.

In the process of removing the carbon trace using scotch brite pads - slow but steady progress. Once we are satisfied that as much of the carbon trace as possible is removed from the ceramic, we'll leak check again and resume tomorrow for installing a new high voltage cable.

Log Number: 4474867Logbook(s): 

• ELOG

Body: 

Replaced 2.5W amp, RFCM and drive is even lower that previous amp removed by 200w CRFP. After several external cable checks, might have to remove klystron drive heliax to check it for losses. Got 1L21 back into HV after several attempts. HV relay could be dirty and not making full contact or we have a loose wire on terminal blocks TB2 that will need checked if we loose HV permissives again. Recovered 1L21-5 but low drive on cavity 7 needs to be checked out. Looks like another 2.5W amp. Chris and Trey.