To the right is shown a plot of TDC value versus E-counter ID(1-384). This a typical distribution for uncalibrated tagger data. This histogram was used to determine the offsets needed by each E-counter to align them all in time. |
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| Here is shown the same distribution after calibration. This was generated using only some of the Pb-glassII data. This looks as expected now allowing for a narrow cut to easily be placed around the band. |
Here is a plot made from events at the begining of the Pb-glassII
data set. The calibration used for the above plot does make a smooth
band. But now, there is a second band emerging and an obvious slope
as you go from low to high photon energies (left to right).
It's important to remember that all of this data came from one run which basically swept the beam through the whole calorimeter before eventually centering it on the center of the array for the last part of the run. This seems to indicate two things:
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