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November 2, 2017 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. Run preparations:
    • CDC update
    • FDC update
      • Threshold upgrade
      • LV not regulating (fixed) [2]
      • HV main frame issues [3]
  1. Tracking
  2. fADC125
  3. Other


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

Run preparations

- Sergey: may be able to start cosmic run with CDC and FDC over the weekend.

- FDC threshold upgrade is done: all modules, cables installed; Hovanes finished the control system. Has to be tested, best with DAQ and software trigger looking at the noise.

- There WAS a problem with one FDC LV module - several channels didn't regulate the voltage. Module was replaced and now is OK.

- There IS a problem with one (of the two) CAEN HV mainframe that has 4 negative FDC modules and three CDC modules. When IOC reads the voltages sometimes (once per day) it gets the information from the module in the previous slot. When the FDC module is readout and gets CDC voltages it engages the software interlock since the CDC voltages are higher than the FDC negative ones. Replacing one module didn't help, decided with Hovanes and Fernando to replace the whole mainframe.


- Mike showed plots (theta vs phi) for different positive and negative particles. There is a striking difference depending on the charge in forward direction - there are many more positive than negative tracks. There's also phi-asymmetry better pronounced for negative tracks. Simon will look into his codes - the two signs must be treated equally.

- Sean showed 2016/2017 comparison plots - # track hist vs theta. It looks like in 2017 there are less tracks with # of hits in some ranges. This requires more studies.


- Naomi still can't get the self-triggering working; P2 triggering has also stopped working; suspects any and all of the modules in the VXS crate. In any case the target has been installed and most likely will not be possible to place iron source inside the CDC before the end of the run.


- TRD status: the entrance window of the TRD prototype has been replaced by a chromium one (much less material) by Brian Kross. The detector has been installed in the Hall, as well as a new VXS crate that will be used as an independent DAQ for the TRD tests.

- Nacer nearly missed the meeting (confusion with the summer saving time), wanted to present his dE/dx studies. He will do it next meeting (it two weeks).