Minutes 5-9-2007

FDC Weekly Meeting

Date: May 9, 2007

Participants: Daniel, Simon, Kim, Roger, Chuck, Tim, Fernando

Next Meeting: Wednesday, May 16, 2007 @ 1:30 p.m.

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Cathode Prototyping

 - DSC raised an issue with our planned carbon fiber support ring
   for the cathodes, namely issues associated with heating due to
   large current flows associated with a magnet quench.  Nobody in
   the room had any knowledge of the issues.  DSC will do some
   investigation by talking to Mac as they have similar issues with
   the planned carbon-fiber endplate for the R2 chambers for CLAS12.

New Prototype Cathodes

 - The delivery of the +/-75 deg U/V cathode boards is on hold as
   CCT marketing (the flex board manufacturers) is having trouble
   making our cathode boards (with the 5 micron Cu strips) without
   having the low resistance problem found on the full scale dummy
   boards.  They will be in contact with Sheldahl to see if this is
   a problem with the board material (although the material that CCT
   has in their possession is the same as they used for our other
   cathode boards), and they will also do some checking of their
   etching procedures to see if they are doing something different
   or wrong.
 - Simon was asked to follow up with CCT to talk to a technical
   representative (as opposed to a salesman) if he does not hear
   from them within a week.  We do not want the delivery of these
   boards delayed.

Circuit Boards

 - Fernando will specify the pin out for the daughter board connectors
   to Roger and Kim so that they can begin laying out the STBs.  We
   are assuming that these will be two-piece boards.  Roger will follow
   up by looking at email exchanges with Brian and then contacting the
   PCB manufacturer before Kim begins work.
 - We decided not to worry too much about daughter board connector
   placement for the full-scale prototype.  At some point Tim and
   Chuck will have to layout the precise locations of the connectors
   to ensure that we have uniform coverage of the cables about the
   perimeter of the FDC system.
 - The LV for the daughter boards will be supplied through the STBs
   themselves.  Fernando will find a connector to use to connect the
   LV lines to the STBs.
 - The design of the HVTBs is awaiting the rate studies from the
   ongoing MC effort.  We are still expecting results shortly.

FDC CD-2 Document

 - Work on this document to address the material issues in the active
   and inactive areas brought up during the drift chamber review is
   awaiting results from MC.  More to come.

Magnetic Field Tests

 - DSC turned in the FDC test plan and request to Volker.  DSC will
   follow up with Volker and discuss the time frame for doing the
   work.
 - We are still trying to find external tracking detectors to define
   a track at the location of the FDC prototype.  No luck digging
   anything up at JLab.  DSC will approach IUCF about what they may
   have available.

Work List

 - The FDC short-term work list has been posted on the FDC web site
   (see http://www.jlab.org/Hall-D/detector/fdc/).  This is continually
   being updated and DSC welcomes any feedback or comments from the group.

Minutes prepared by Daniel. Send any comments or corrections along.