Minutes of the Feb 24, 2005 US ROD meeting

Probably incomplete as I (CC) missed part of the meeting due to technical difficulties

Presentation by Yuri

I missed this due to technical problems. This is a report by Yuri:

Bad channel data for 8 rods have been compared with module test results

due to lack of proper analysis software this was done manually (raw noise)
most of the marked bad channels were confirmed by MRT data
there were some open sensors that were not confirmed
there were some additional bad channels found
there were bookkeeping mistakes and one misprint found, corrected

I asked Lenny to remove 2 modules on rods 32 and 227 (December lot) and
re-test them. Will use Patrick's DefAna to analyze data taken with these rods
at cold temperature and from CalProfRuns to have more detailed
characterization of these rods. These plots will be added to a set of plots I
assembled using ARCS macro modified by Ryan.

Conclusion: there is a general agreement with MRT and ARCS data. It is
necessary to investigate the reason for observed differences, especially for
2 modules that performed badly (December lot).

And here are Yuri's slides.

Follow up on pending action items from last week's meeting:

UCSB: can we improve humidity to go to lower T in multirod?
Air dryer on order

Want to read all DCU out, put in root file.
Ryan modified SR macro to spit them out, still needs nominal calibration constants. Still on the list.

Hardware to check all rod monitoring
Some parts already in. Others should be here shortly

Standalone redundancy ring check
Decided to move to SR. Ryan will make it work. Still on the list

Defect analyzer for MR
Patrick: ready to go. UCSB will install it and try it out.

Jim to start talking to JT about scripts for ARC/ROD comparison
No news

Yuri to talk to Wim, figure out what DAQ settings should be
Done (I think?)

UCSB to test a few bare rods
See no problems. FNAL to repeat test with identical procedure.
If FNAL rods still bad, will send to UCSB to double-check

Worse noise in the cold at UCSB Seems to still be there. Will try more robust grounding.
LV supply current is OK.
Jim points out note about different chip settings in the cold. He tried them, seem OK
Make sense to adopt them. FNAL will try them also.
See UCSB elog entry also.

Stability Issues on MR

Stability OK.

Noise

See action item 9 for cold vs warm at UCSB. No info from FNAL yet.
FNAL MR noise OK, i.e., opens behave as they should.
Agreement to try normalization to charge injection in order
to have quantitative measure of noise independent of laser gain,
e.g., see UCSB elog.

Other items

Patrick sees some strangeness in FNAL calprof runs.
Some due to pedestal floor, but other problems too.
Jim has seen clipping due to pedestals too,

Some discussion of grading scheme for rods.
Valeri et al have asked for input. Will have to deal with this soon

Yuri reports anomalous high leakage currents on SS6 rods.
Looks OK at UCSB (?)