Taking Pedestal Data » History » Version 77

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Rick Tesarek, 07/08/2011 02:18 PM

Taking Pedestal Data

To take pedestal data first stop DAQ. This includes:

  1. End the current run
  2. > (closing all Run Control GUI applications)
  3. > stopSystem (stopping all DAQ applications)
  4. WAIT until the System is stopped!
  5. > @reboot-dcm-all
    1. Wait until the DCMs turn red and then pink
  6. If the scan is to be taken with cooling enabled, run the "Cool
    DCM" script from the icon on the NOVA_DAQ-2 desktop. Wait for the cooling to stablize then proceed with the steps below.

After this we are ready to take the pedestal data.

  1. Locate the "Run Pedestal" icon on the NOVA-DAQ-1 computer (the very left one in the Control Room).
  2. Double-click it.
    After ~ 5 seconds a Pedestal Data Runner application window will appear:
  3. Press the "Go" button.
  4. Wait for ~ 1 minute. Sometimes you need to press the "Go" button a couple of times to get the progress bars going.
  5. After about a minute the progress bars on the DCMs will start moving toward to 100%. It would look something like this:
  6. Fill in start_pedestal_run form in the ECL when the pedestal run has started ( output dir should include day/month/year hour:minute as shown in the pedestal run window).
  7. Keep an eye on how the pedestal run is processed:
    dcm-11 and dcm-13 are half channel populated, so they should go roughly twice faster than other DCMs (see how it looks like on the picture above).
    It should take ~ 12 minutes for the run to be finished. During this time the temperatures of the APDs will not be correct on the TECC monitoring screen.
    If at least one DCM behaves not as described, see Troubleshooting section below.
  8. Wait for ~ 12 minutes until the data taking finishes.
  9. After all DCMs finish the DSO readout (100% everywhere in the status bars, Run Status - "DSO readout finished. Reprocessing in progress"), the data reprocessing starts to produce thresholds, pixel masks, etc.. At this point one can start a normal (DCS) data taking if there is no intention to apply new thresholds and pixel masks. Do not kill PedestalDataRunner, though - let it finish the reprocessing!
  10. After one sees "Run Status" as "DONE", then we are done with taking the Pedestal Data.
  11. (Optional) After reprocessing is finished, two additional buttons will appear at the bottom of the PedestalDataRunner window: "View Results" and "Load To Database".
    So, one can now view results of the DSO scan and Load them into the Database by pressing these buttons.
  12. Close the Pedestal Data Runner window.
  13. We're almost done... now do another reboot of the DCMs as shown above (reboot-dcm-all).

Loading New Enable Masks and Thresholds in the Database

The DSO scan will generate a set of FEB and Pixel Masks along with Threholds. Following the scan these values should be checked and if deemed to look reasonable, loaded into the database prior to the next run. The steps below describe how to both validate the data and load it into the database.

Validate the scan:

  1. From nova-daq-2 launch the Check DSO Results scpirt by double clicking on the check mark icon.
  2. Three root canvases will open showing the FEB Enable masks, Pixel Enable Masks, and associated threshold values.

    Compare these to the previous plots which should have been posted into the logbook -- they should have been tagged as "DSO/Pedestal Scans" so you can search by that.
  3. Post a screen capture of these plots into the logbook. Make sure to tag the entry as "DSO/Pedestal Scans" so the next shifter can find it easily to compare. Save the snapshots to /nova/data/shift/dso so that the files are visible from all control room machines.
  4. Close the plots by selecting "Quit ROOT" from the File dropdown of any of the three plots. (DO NOT close using the x on the terminal window.)
  5. If everthing looks reasonable proceed to load the masks and thresholds.

Loading Masks and Thresholds:

While logged on ctrl-master as novadaq

  1. Execute <date string>
    [novadaq@novadaq-ctrl-master ~]$ 2011-04-12_08_19_18
    11329 pixels have threshold values defined.
    483 FEBs have pixel masks set.
    11 dcms have FEB masks set
    Press return key to load into database or ctrl-c to abort...
  2. If a resonable number of pixels, febs, and dcms are reported. Press enter to finish the load. You see the following lines:
    Loading into nova_prod on at port 5433 ....
    Reading /data/PedestalData/PedScans/2011-04-12_08_19_18/febmask_2011-04-12_08_19_1
    Reading /data/PedestalData/PedScans/2011-04-12_08_19_18/pixelmask_2011-04-12_08_19
    Reading /data/PedestalData/PedScans/2011-04-12_08_19_18/thresholds_2011-04-12_08_1
  3. Once the prompt is returned to you you're finished! The next run should use these latest masks and threshold values.


The pedestal data run lasts for ~ 12 minutes. If it takes much less or much more than that try to
  • Close Pedestal Runner Window
  • Reboot the dcm's by reboot-dcm-all or, if necessary, power-cycle the dcms.
  • Retake pedestal data.

If that still does not help, contact Denis Perevalov. NOvA phone Book

Instructions for experts