Minutes-6-16-2011

June 16, 2011 FDC meeting

Agenda

1. Production (Dave)
   • First chamber tests pic1, pic2 (Lubomir)
   • Second set wire frame and cathodes
   • Other
2. Engineering (Bill)
   • New encoder
   • Gusset ring
   • Other
3. Electronics update (Fernando, Chris)
4. Chamber testing at EEL126 (Beni, Lubomir)
5. Other

Minutes

Participants: Eugene, Bill, Glenn, Dave, Chris, Beni, Simon, and Lubomir.

Other

At the beginning of the meeting Bill and Dave, representing also other non-physicists, expressed interest in learning more about drift chambers, GlueX detectors and physics and beyond. Eugene, Simon, Beni were happy to answer their questions. We all agreed also to organize a special presentation for them.

Production

- The pictures linked above, show the configuration of the first chamber package and the testing set-up. After taking the wire frame form the vacuum chamber (vacuum went down to ~6 10^-6 tor) we checked that the frame was no longer conductive and we installed it again in the package. First we had Lexan sheet on the top, than we replaced it with the second cathode and the second end window. The package has no detectable gas leakage and we bubble it with a flow of 20-40 ccpm. On three of the HV sectors (out of four) we were able to apply HV up to 2300V and -500V sense/field with current less than 100 uA. The fourth HV sector shows high current so far: ~500 uA at 2000V/-500V. It may improve but it may require cleaning. In any case the chamber is operational and we tested all the channels with a scope with differential probe.