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Common Mode Noise calibration for PS modules

Irene Zoi requested to merge izoi/Ph2_ACF:cmNoisePStemp into Dev

This calibration allows the measurement of the common mode noise in PS modules. Since the CIC is used in sparsified mode, no more than 128 clusters per pixel and per strip per hybrids are allowed. Thus the threshold to perform the common noise measurement is set such that ~ 64 channels per pixel and 64 channels per strip should fire at the same time. The strategy is:

  1. trim the module near the pedestal. This is obtained performing the calibrationandpedenoise measurement using the settings defined by Kevin Nash in https://mattermost.web.cern.ch/cms-exp/pl/ysipukfu7j878jz1he3fsj8bqc and reported here for convenience.
<Setting name="FullScan">1</Setting>
<Setting name="PedestalEqualizationFullScanStart">220</Setting>
<Setting name="PedestalEqualizationPulseAmplitude">20</Setting>
<Setting name="PedeNoisePulseAmplitude">20</Setting>
<Setting name="PedestalEqualizationPulseAmplitudePix">20</Setting> 
<Setting name="PedeNoisePulseAmplitudePix">20</Setting>

Note: in the module I used, 20 did not work for the MPAs (Pix), but 30 was ok.

From this calibration, the noise measurement is obtained and saved in the output xml.

This steps is slow and takes about 40 minutes per module.

  1. perform the injectionDelayOptimization starting from the xml obtained in step 1. In this way the pedestal is obtained and saved in the output xml. It takes about 4 minutes per module. Can be reduced reducing the delay range.
  2. Run the commonNoisePS calibration starting from the XML obtained in step 2. The calibration first set the threshold to have the desired number of channels firing based on the pedestal and noise obtained in the steps above. Then it takes a certain number of events (that can be configured in the XML OTPScommonNoise_NumberOfEvents). The common noise measurements takes ~ 1 minute per module.

How many times a certain number of hits is obtained in the different chips, hybrids and modules is saved. Correlations between strips and pixels are also obtained.

Note: the variable TOTAL_CHANNELS_OT has been removed as it corresponded only to the total number of channels in 2S modules.

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