Calibration Check

The CalDB_*.root produced by the decoding program may have a size of almost 800k on disk. Please be sure of that. From time to time a short calibration (only 800 byte) could appear: Delete it (subtle bug in the decoding)!

The CalDB_*.root can be opened by the MonitorUI application, available from every point in the pocc. Simply type:

MonitorUI CalDB _1281323717.root

A display similar to the one in attachment wil appear. From this interface you could alternatively observe:

  • cumulative distributions: pedestals, sigmas, status bits
  • ladder-by-ladder distributions: pedestals, sigma, common noise, occupancy, TDR code, Power Failure status, eccetera
  • comparison with past calibration: if you can choose a reference file to campare the calibration with it.


This is the first plot appearing in the calibration monitor. Here you can find in the pedestals, sigma value and status bit cumulative distributions for all the ladders. In red the distribution for the n-side, in blue the one of the p-side. In this example is displayed a calibration from the August 2010 beam test. The distribution show are a typical example of a good calibration.


This is another summary plot with a typical calibration. Here are depicted the number of bad strips as a function of the ladder number, and the average noise on the p/n side as a function of the ladder number. You can see clearly the presence of a dead (zero-noise) n-side. This is the well known problem of the +405 ladder. You can also see that some ladders are more "noisy" than the others as the -405 and the -907. Their n-side will be probably completely masked.

When a calibration is produced pease check this two display carefully. If you are able to see a big differenc (half of the tracker is missing, or only a particular crate, ...) ask for another calibration. If you are able to see zeros or high values associated to a particular ladder not mentioned in the list of the well-known bad ladders please inform a Tracker expert.

Ladder by Ladder Check

You can also check the calibrations ladder by ladder. This is not strictly required for the fast check, but can be useful. As an example you can observe a view like this one:


Here you can find information about the DSP code number, the threshold applied, the pedestal, sigma raw and sigma. The bad strips are also presented in blue (noisy) or dead (green) in the right plots. in attachement to this page you can find a complete reference calibration from the Test Beam of August 2010.

Calibration Reference Comparison

in the directory:


you can find several calibrations taken along this years (from 2009 up to now). In the README file there is a description of the calibrations stored. You can compare this calibration with the one you are observing choosing from the File Menu > Open Referrence File one of that calibrations. Choosing from the CalMenu the view CalFinder you can easily compare the actual calibration with the old one (mirrored).


Topic attachments
I Attachment History Action Size Date Who Comment
PNGpng CalFinder.png r1 manage 48.7 K 2010-08-17 - 01:05 AlbertoOliva CalFinder
PNGpng CalSummary1.png r1 manage 53.1 K 2010-08-17 - 00:32 AlbertoOliva CalSummary1
PNGpng CalSummary3.png r1 manage 49.5 K 2010-08-17 - 00:32 AlbertoOliva CalSummary3
PNGpng Calibration1.png r1 manage 54.8 K 2010-08-17 - 00:54 AlbertoOliva Calibration1
Postscriptps r1 manage 9835.9 K 2010-08-17 - 01:12 AlbertoOliva A Reference Calibration from TBAug2010
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Topic revision: r2 - 2010-08-17 - AlbertoOliva
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