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April 19, 2018 Drift Chamber meeting


  1. Instructions for Bluejeans meeting connection
  2. Meeting ID: 290664653

Headline text

  1. To join via a Web Browser, go to the page [1]


  1. CDC update [2] [3]
  2. FDC update
  3. fADC125
  4. Other


Participants: Naomi(CMU), Eugene, Simon, Alex B., Sergey, and Lubomir (JLab).


-Naomi showed plots with several noisy preams with some double-peak structures. Nick looked with a scope at these during the last access, but could not reach the preamp cards being behind the UFO shielding. However, it turned the second noise band disappeared after run 42188, which is when Nick was in the Hall, maybe it was a bad connection of the cable on the fADC.

- We looked once more at the material scan. Sergey explained the results in more details looking not only at the "photons" but also at the other background signals. Their suppression is not as big as the one for the photons.

- Changing the hole from 5 to 3.4mm resulted in a reduction of the FDC current (by ~35%), but the CDC current remained similar. Eugene's explanation is that since the current in the CDC comes from both synchrotron and bremsstrahlung, they compensated each other - synchrotron increased by a factor of 3 (beam current increase), while the bremsstrahlung was reduced due to the smaller hole.


- Sergey plans to do similar signal analysis for the FDC, as well.


- Sergey showed the effect of the filtering of the "photon" signals on the rho/omega yields as calculated by Simon. Combined with timing cuts, it improves the yields up to 60%.