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Recently the new charge injection calibration data was collected. I have compared 2010 CI calibration with one collected on orbit in 2009  and on the ground in 2008.
The difference in ADC response  between 2010 and 2009 calibrations as a function of injected charge in DAC units is shown on the following plot for "typical" channel twr=0, lyr=0, col=0, face0 in LEX1 range (this range has the biggest deviations from linearity and for it the charge injection calibration is the most important):


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Similar difference for the same channel between 2009 (orbit) and 2008 (ground) is following:

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In both cases the difference between two charge injection calibrations is mostly linear and is ~0.2% for 2009 - ground difference and several times less for 2010-2009 difference.

The histograms of linear slopes for all 3072 LEX1 channels is show on next two plots for 2009-ground and 2010-2009 comparison, respectively: