Difference between revisions of "Minutes-7-24-2014"

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== CDC update ==
 
== CDC update ==
  
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- Beni studied the noise  
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- Beni studied the CDC noise once again (all the results are linked above): using a scope on one channel (#4 connector C6) with a stand alone DC power. He made measurements in different conditions: turning on/off LV/HV the power for the crates itself and also ramping the HV. He was looking for is 60Hz noise and 200kHz bursts with tens of MHz within the bursts. The conclusion: the 60Hz comes when powering the south HV supply (connected to the card). The 200kHz bursts come when rumping up the HV and stay when the HV is up.
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Fernando wanted more tests with more cards and HV modules to see if this is a problem with a particular module/HV crate or a common feature of this CAEN system.
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- Mike found that for the channels with no signals in the fADC but visible on the scope,  one can actually see something (noise or signal) in the fADC but with a huge DAQ offset of 0xd000. It is not clear yet what is the quality of the signals.
 
   
 
   
 
== FDC update ==
 
== FDC update ==
  
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- Lubomir presented a table (xls file linked) with all the problematic cathode channels as identified from the latest DAQ runs. Luke checked these channels with a scope which information is included in the Q-column with color. Information about Anatoly's measurements with scope in March/April (right after insertion) and the attempts to fix these channels is also included. 
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- The first track going through all the 24 chambers is shown above. It was obtained with Beni's horizontal muon trigger. So far within 4 hours run we found only two such events. There are few more with muons partially crossing the FDC system. Still, this one event help a lot to fix the geometry, the translation table and some bugs in the code. Important is that we see signals from all the cells and all the planes within a cell, upper, down strips, and a wire, crossing at the same point, meaning we have 100% efficiency.    
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- For 69 of the channels (pink or red color) we suspect the problem is at the detector side (mostly conductive tape, but also connector or pre-amp issues). In the packages (1 to 4) the number of such channels is 4,1,41,23. Ten of these channels were OK in April, but had problems before, except two of them.
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- We have 11 channels (green) where we see signals with the scope but not with fADC. However, the fADC channels are OK with another cable; Fernando suspect cable/connector problem. In the fADC data you see overflow or a fixed value at ~2000 and Beni made a list of such channels before.
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- Finally, there are 9 channels (yellow) with no signal, but also almost no noise. Some of these were identified before to have problems with the 3M connectors, but the rest may have other issues.
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== Electronics ==
 
== Electronics ==

Revision as of 12:45, 25 July 2014

July 24, 2014 FDC+CDC meeting

Agenda

  1. DAQ (Beni)
  2. CDC status (Mike, Beni)
  3. FDC status First Track through all packages (Lubomir)
  4. Electronics (Chris, Nick)
  5. Cathode scan (Luke)
  6. Other

Instructions for Bluejeans meeting connection

FDC meeting ID: 290664653


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