Difference between revisions of "Minutes 1-31-07"
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− | + | ==Cathode Mechanical Mockups== | |
- A second cathode frame has been made up and Brian will attach this | - A second cathode frame has been made up and Brian will attach this | ||
to the first on Monday of next week to complete our first mechanical | to the first on Monday of next week to complete our first mechanical | ||
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these boards. | these boards. | ||
− | + | ==STB/HVTB Design== | |
- Daniel has prepared a list of design rules of thumb for Kim and | - Daniel has prepared a list of design rules of thumb for Kim and | ||
Roger to provide general guidelines for the design of the HVTBs | Roger to provide general guidelines for the design of the HVTBs | ||
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portal and give copies to Roger and Kim. | portal and give copies to Roger and Kim. | ||
− | + | ==FNAL Visit== | |
- DSC reviewed some lessons learned from the FNAL visit made last | - DSC reviewed some lessons learned from the FNAL visit made last | ||
Thursday (DSC, Simon, Brian, Tim went). He will prepare a write-up | Thursday (DSC, Simon, Brian, Tim went). He will prepare a write-up | ||
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length, ground plane layout, etc. | length, ground plane layout, etc. | ||
− | + | ==Chamber Design== | |
- Tim pointed out an issue with the layer design that looks like it | - Tim pointed out an issue with the layer design that looks like it | ||
leads to different half gaps on either side of the wire plane. We | leads to different half gaps on either side of the wire plane. We | ||
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thinner. Perhaps we could ultimately get back to the 5 mm half-gap. | thinner. Perhaps we could ultimately get back to the 5 mm half-gap. | ||
− | + | ==Thermal Simulations== | |
- Fernando provided a write-up to the collaboration regarding his work | - Fernando provided a write-up to the collaboration regarding his work | ||
on the thermal simulations. He has asked us all to read this and | on the thermal simulations. He has asked us all to read this and | ||
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this. | this. | ||
− | + | ==Cable Issues== | |
- Joe provided an update on his work to layout the cables, initially | - Joe provided an update on his work to layout the cables, initially | ||
around the FDC itself, and also on routing the cables to the | around the FDC itself, and also on routing the cables to the | ||
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as not to bias the physics. | as not to bias the physics. | ||
− | + | ==Amplifier/Shaper== | |
- Gerard has been working with Simon all week on implementing the | - Gerard has been working with Simon all week on implementing the | ||
shaper board into the FDC test set up. Based on the initial | shaper board into the FDC test set up. Based on the initial | ||
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board. | board. | ||
− | + | ==Monte Carlo Meeting== | |
- DSC and Simon will meet with David Lawrence tomorrow to discuss | - DSC and Simon will meet with David Lawrence tomorrow to discuss | ||
work on the GEANT Monte Carlo, especially with regard to preparations | work on the GEANT Monte Carlo, especially with regard to preparations |
Latest revision as of 09:04, 12 April 2007
FDC Weekly Meeting
Date: January 31, 2007
Participants: Daniel, Tim, Roger, Fernando, Kim, Simon, Brian, Elke, Chuck, Gerard, Joe
Next Meeting: Wednesday, February 7, 2007 @ 1:30 p.m.
Contents
Cathode Mechanical Mockups
- A second cathode frame has been made up and Brian will attach this to the first on Monday of next week to complete our first mechanical cathode sandwich mock-up. - The full-scale tensioning system was used to stretch a 6.3 micron sheet of aluminized mylar on one of our g10 frames. The process went quite smoothly as long as the mylar sheet had no defects in it. Any defect in the material would cause a rupture in the sheet as it was being tensioned. - The aluminized mylar had 250-300 angstroms of aluminum on each side. If this is acceptable for a ground plane, we will use this material for final cathode construction. - A meeting with the JLab survey group is schedule for Thursday at 10:00 a.m. to talk about measuring the flatness of the cathodes in preparation for the upcoming chamber review. - Brian received a call from the company manufacturing our dummy cathode boards (those with the copper strips). They should arrive within two weeks. - We will make our second cathode sandwich using these boards. Brian is concerned that the copper will have some impact on the procedures developed for the naked kapton sheets. - Gerard suggested that we measure the capacitance of the strips on these boards.
STB/HVTB Design
- Daniel has prepared a list of design rules of thumb for Kim and Roger to provide general guidelines for the design of the HVTBs and STBs. - The list has been passed on to Fernando and Gerard for comments before we pass this on to Kim and Roger. - Once they receive this list they will get back to work on the layout of the STB. - Gerard pointed out an oversight on the HVTB design that DSC passed around. He will fix this and re-post the document to the GlueX portal and give copies to Roger and Kim.
FNAL Visit
- DSC reviewed some lessons learned from the FNAL visit made last Thursday (DSC, Simon, Brian, Tim went). He will prepare a write-up for the collaboration. - We discussed some of these at the meeting. This includes solder pad size, modifications to the STB, sighting marks, solder pad length, ground plane layout, etc.
Chamber Design
- Tim pointed out an issue with the layer design that looks like it leads to different half gaps on either side of the wire plane. We need to see a complete mechanical drawing to make more sense of this. - DSC stated that the half-gap can be no larger than 6 mm. The 6 mm half-gap is actually defined by the height of the daughter board connector (believe it or not). Gerard suggested that we contact the connector manufacturer and see if the connector can be machined thinner. Perhaps we could ultimately get back to the 5 mm half-gap.
Thermal Simulations
- Fernando provided a write-up to the collaboration regarding his work on the thermal simulations. He has asked us all to read this and provide feedback. - Gerard stated that basing the thermal cooling system on an assumed 40 mW/channel power dissipation of the ASICS could be a worry. Given that we may still be several revisions away, the power dissipation could go up. - Fernando stated that the current cooling system design is marginal even for the 40 mW/channel number. - We discussed the idea of liquid cooling again, and we may have no choice but to move in this direction. Tim, Elke, and others cited that this is a standard design and we should not be too worried by this.
Cable Issues
- Joe provided an update on his work to layout the cables, initially around the FDC itself, and also on routing the cables to the electronics. - Joe now has the spec. sheet for the 50-conductor cables that we are considering (I assume this is the halogen-free version). He will provide budget numbers in the next few days. They will cost more than the simple shielding cables currently in the FDC budget document. - Joe and/or Tim will produce an engineering drawing shortly to make it clear how tight we are on space outside the FDC. - Elke made it clear that the cables will have to evenly surround the FDC system to provide a uniform thickness in all directions so as not to bias the physics.
Amplifier/Shaper
- Gerard has been working with Simon all week on implementing the shaper board into the FDC test set up. Based on the initial studies, Gerard has prepared a second board with improve performance from the standpoint of gain, rise time, and tail cancellation. - Simon is working to provide resolution numbers for the new board.
Monte Carlo Meeting
- DSC and Simon will meet with David Lawrence tomorrow to discuss work on the GEANT Monte Carlo, especially with regard to preparations for the upcoming tracking system review (March 6,7,8).
Minutes prepared by Daniel. Send any comments or corrections along.