[Halld-tracking-hw] Tracking Meeting Minutes Posted

[Naomi Jarvis]

Minutes are online at https://halldweb1.jlab.org/wiki/index.php/January_16,_2013_Tracking_CDC/FDC

Text below

Present: Curtis, Naomi, Beni, Simon, Lubomir, Eugene, Mark

Collaboration meeting
3 talks have been reserved for tracking
FDC Update
Last production package (#2) assembled. Gas pressure lower by 10-20% than in the other packages at the same flow, could be due to the new manifolds since no gas leak was found.
Package #4 is being tested at JLab. It held the nominal HV right from the beginning without any trips. Beni: all the wires and strips already tested and working fine except 4 strip channels showing somewhat lower signals.
Decided to build 6 spare cells. Will chose 6 wire frames out of 7 with some of them showing elevated dark current. We have also the material for 12 cathodes.
CDC Update
CDC construction has been stalled pending the arrival of the transfer ring (STOP PRESS the shipment of this was authorized this afternoon - wahoo!)
Naomi measured pedestal widths of the HVB & preamp combinations inside a grounded metal box and found that the pedestal width of the original HVB and preamp4 was only 2 fADC units, after altering the HVB to attenuate the input charge to the preamp and later removing the preamp's terminating resistors to match its range to that of the fADC we now have a pedestal width of 15 fADC units, before adding any pickup from the chamber (pickup from the prototype now adds only 1-2 fADC units). The increased pedestal width was not so obvious at the time because the noise from the prototype was dominated by pickup from the thermocouples (since removed).
Eugene requires an estimate of CDC completion date and costs to completion. CMU's contract needs to be extended to allow the CDC to be tested at CMU until Hall D is ready to receive it (probably in August). Testing was included in the original contract but the original delivery point is April.




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