Crew Chief Shift Log, 2025-06-29 DAY
Start of shift: Beam to xABCD.
Start of shift: Beam to xABCD.
It was noted that the 1L23 NDX neutron rates jumped this morning, right around the time 1L23-8 quenched multiple times and had to be derated. Gradually adjusted the GSET, and sure enough the cavity had popped a field emitter. Derated it a further 1.3 MV/m to reduce neutron rates 2.8 rem/hr. Not quite back at previous levels, but at the 1 MV/m : 1 rem/hr limit.
The OPS DRVHs for the following cavities have been updated:
1L23-8
Username: alexs
Date/Time: 06-29-25_14:14:00
RF Status: Good
Tuner Status: Good
Comment: DRVH=10.000 Derated 1.3 MV/m for 2.8 rem/hr neutron reduction
Previous OPS DRVH: 11.3
Special Instructions:
Noticed the external transformer for 1L13 in the NLSB is radiating a significant amount of heat. Could likely use more airflow. There's a fan nearby it not currently turned on, but I didn't want to risk poking the bear on a Sunday afternoon when it could wait until Monday.
The OPS DRVHs for the following cavities have been updated:
2L17-8
Username: benesch
Date/Time: 06-29-25_09:26:21
RF Status: Good
Tuner Status: Good
Comment: DRVH=4.100 Arc Rate Management four at 4.25, equally spaced
Previous OPS DRVH: 4.25
Special Instructions: