Difference between revisions of "Minutes-10-23-2014"

From GlueXWiki
Jump to: navigation, search
Line 36: Line 36:
 
== CDC update ==
 
== CDC update ==
  
−
<!--
+
- Mike is working on the dac/pedestal calibration.  Simple slope extrapolation doesn't work. He is using a standalone code with Beni's DAQ, that will be used for checking the rates when the main DAQ is not working.
  
−
- Mike is working on the efficiency plots, also charge vs track length, to be used for gain calibration.
+
== FDC update ==
  
−
- The Bertan modules (supplying HV to two cards) will be left ON before the start of the beam alignment with a thresholds of 1 uA.
+
- Tim: next week we will have the results from the last FDC survey, namely z-positions and plane angles, SEPARATELY for each package.
−
 
+
−
== FDC update ==
+
  
−
- Vald made presentation (attached) about the strip gain calibration. You use the fact that the sum of the charge on the down strips is the same as on the upper strips. Another more important fact is that  we know the shape of the charge distribution over the strips.  Vlad presented results for the calibration coefficients of the third package as tested in EEL126. The gain varies by about +/-15%, smaller fraction of the variation should come from the electronics (Fernando).
+
- Vald showed
  
 
== Commissioning ==
 
== Commissioning ==
  
−
- Simon and Lubomir presented their proposals for monitoring histograms. After some discussions, we agreed to have profiles of the wires and strips for each cell and package. Possibly, later, we can put the same information in 2D plots. We will also have the drift time spectra for each cell.
+
- Simon did a plugin for the FDC online monitoring, showing the strip and wire profiles as discussed last time. Wire profiles were OK, but not the strips because of some noisy channels (due to wrong dac values for example). Lubomir continued working, adding more information to the code using some position and timing correlation between the two cathodes and the wires to filter out the noise. While the position correlations are OK, there are inconsistencies with the timing correlations. In addition, due to the lack of the trigger time (not yet implemented in JANA/DANA frame)
  
 
-->
 
-->

Revision as of 16:11, 23 October 2014

October 23, 2014 FDC+CDC meeting

Connection

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

Agenda

  1. DAQ (Beni)
    • f125 status
  2. Electronics (Fernando)
  3. CDC update (Mike)
  4. FDC update (Vlad, Lubomir)
  5. Commissioning Wiki Page (all)
  6. Other

Minutes

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

DAQ and electronics

- Cody generated a new version of the firmware that is much more stable, as Beni tested it over the last night. With the new firmware Sasha was also able to have the CDC crates running at >1kHz without crushes for some time (before, they crushed at about 300Hz). However, with the new firmware, some new modules started showing problems, as tested by Beni and Sergey. A chip-scope was installed on the last module of ROCFDC5, but turns out other modules were crushing the DAQ now.

- Fernando explained the changes in the firmware: in the previous version, Cody let the CAD software do the planing of the changes (in particular going from 16 to 72 channels) to the f250 firmware. As a result, some of the clocks were not routed in an uniform way. Now Cody manually required a separate (clean) area to be used for the clock distribution.

- Cody: the new bad modules are most likely related to a different problem, could be a hardware problem. We are not confident in the quality of the boards (Fernando). The first article f125 from the new vendor will arrive next week.

- Eugene: For the first days of running we should simply exclude the bad modules from the DAQ till we find (if any) a stable configuration that runs for at least an hour without crushes. Then, during the several days of down time we may tray to fix/replace the bad modules. At least for the first days, the main priority will be to have the DAQ working in any configuration (even without the chambers!). Then we can think of how to test the detectors, which may be postponed till December.

- Bryan Moffit is working on a software reset of the module if it crushes, so the you re-sync the events and can use the information from the module further without stopping the DAQ.

CDC update

- Mike is working on the dac/pedestal calibration. Simple slope extrapolation doesn't work. He is using a standalone code with Beni's DAQ, that will be used for checking the rates when the main DAQ is not working.

FDC update

- Tim: next week we will have the results from the last FDC survey, namely z-positions and plane angles, SEPARATELY for each package.

- Vald showed

Commissioning

- Simon did a plugin for the FDC online monitoring, showing the strip and wire profiles as discussed last time. Wire profiles were OK, but not the strips because of some noisy channels (due to wrong dac values for example). Lubomir continued working, adding more information to the code using some position and timing correlation between the two cathodes and the wires to filter out the noise. While the position correlations are OK, there are inconsistencies with the timing correlations. In addition, due to the lack of the trigger time (not yet implemented in JANA/DANA frame)

-->

Retrieved from "https://halldweb.jlab.org/wiki/index.php?title=Minutes-10-23-2014&oldid=61177"