More on Raw BSMD ADC Distributions
As Will pointed out, you can't always say with 100% certainty whether a given module is showing banding structure just by looking at the raw ADC vs. channel plot. Jan suggested that it might be possible to look at this in a more systematic fashion by fitting an exponential to the range [400, 950] of the projected ADC distribution for channels 1-150 and 151-300, e.g.:
or
and then plot the chi2/dof of the fit. The result of this is below:
The modules that were under the old configuration clearly stand out, as do a handful of others. And the difference between modules 112 and 33 (channels 1-150), which are plotted above, is fairly pronounced. However, this plot suggests that this method cannot be used to split the modules into those showing banding and those not showing banding, though it does show which have a greater or lesser degree of it.
Note that module 97 channels 1-150 and module 106 channels 151-300 have had their chi2/dof values set to 0 in this plot. That is because they would dwarf the rest of the plot if they were included: the raw plots and ADC projections are shown below.
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