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February 11, 2016 Drift Chamber meeting


  1. Instructions for Bluejeans meeting connection
  2. Meeting ID: 290664653
  3. To join via a Web Browser, go to the page [1] https://bluejeans.com/290664653.


  1. Collaboration meeting Feb 2016
  2. NIM Papers
  3. Run Readiness Run Coordination Meetings: Spring 2016 Run
  4. Electronics (Fernando, Chris, Nick)
  5. Other


Participants: Naomi, Mike (CMU) Luke, Fernando, Eugene, Cody, Chris, Simon, Beni, Nick, Sergey, and Lubomir (JLab).

Collaboration meeting

- The agenda is finalized: three talks from Mike, Simon and Sergey.

NIM papers

- Mike demonstrated the nice features of the new ShareLaTex tool, other than that no recent progress with the papers.

Run Readiness

- Mike showed his latest results on the CDC performance. The efficiency vs drift distance is now flat (at a level of 90-92%) and dropping at the end due to the tube deformation, i.e. in some places the maximum drift distance is shorter. Eugene: why the efficiency is relatively low; this is with cosmics and Mike has to check all the cuts. Mike discussed also other efficiency plots as function of delta, the tube deformation parameter.

- CDC is now at 2100V. The HV scan will start from 2125V down with a step of 25V; the end of the plateau is at 2075V (Naomi).

- Luke updated the FDC table with problematic channels (table linked above). Some new noisy (mostly wire) channels appeared. We have seen this before. This is because the discriminator threshold is kept close to the noise level. If require signals from the corresponding strips, the noise disappears. Also have in mind that the noise is seen on the top of the cosmic signals, and its frequency is low enough for the beam signals.

- Lubomir looked at the average charge vs drift time from a run in December 2014 (plot above). The drop of the charge with the time indicates some recombination. We measured the Oxygen level to be <20ppm, but there might be other electronegative gases. Eugene: need to find when was the last time when the plot was OK. Lubomir will study this. It also emphasizes the need for a monitoring chamber.

fADC125 firmware

Naomi chaired this part, the minutes are here.