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[videbaek <videbaek AT bnl.gov>]

TPC meeting December 4, 2025
Present: Alexei, Gene, Jim, Yuri, Flemming

Hardware:

One Caen power supply for anode had to be exchanged
Gridleak PS lost communications. Access needed to r-establish comm.

Anode voltage scan done with 4 settings going down from nominal ~1 M MB 
events per scsn, 5 min each. Successful. Interestingly the 11-8 which 
had been lowered from nominal to 1100V held at 1390V.. TPC anode sector 
7 channel 6 is set to 1345V (instead of 1390V)

Discussion on gas flow N2 vs Ar during temp shutdown from Dec 9 to Jan 
6. Alexei will review Ar capacity needed. We have sufficient Methane for 
the max 3 weeks of operation needed for the 3-4 day FXT low energy run.
Electroncs: Usual steady state. With mask/un-mask
Software:

Gene mentioned that no ingoing activity but could start run25 SC 
corrections soon after run end on Dec8.

Yuri had continued de/dx behavior seen in run 23 de/dx for physics vs. 
mtd streams. Seems partly related to new clusterfinder and increased 
number of flagged (deconvoluted) clusters. Could be some gain by 
included flag clusters in de/dx calc with increased efficiency , but 
worse de/dx. No presentations yet. Showed some tables and plots.

Discussion on needs for final calibrations, surveys needed after run.
Gene suggested we mingth try to look at omegate-tau calibrations (needs 
cosmics+gas)
Alexei suggested an improved mechanical survey (after RDOs removed).
Adjourned at 12:34




--
Flemming Videbaek
senior scientist, emeritus
videbaek @ bnl.gov
Brookhaven National Lab
Physics Department
Bldg 510D
Upton, NY 11973

phone: 631-344-4106
cell     :  631-681-1596