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It is visible in January 2009 in CAL hits map for tower/layer: 
as well as in hits map for tower 4, :
while in September 2008 it wasn't there.:
This extra occupancy in one crystal is caused by increasing pedestal noise in LEX8 range of this crystal end. The fact that the noise in this channel is "out of family" was noticed yet during the ground test, but at that time it was not big enough to visiblly affect the occupancy. But the noisy in this channel was increasing on orbit - see pedestal width trending plot for all channels over 5 month:
The channel with bigest pedestals noise ~40 LEX8 units (1.3 MeV) in November 2008 on the top 2d histogram is tower=4, layer=3, column=3, face=0; the second "out of family" channel is tower = 6, layer=4, col=1, face=0, pedestal noise~23 LEX8 ADC units (0.8 MeV). The average pedestal noise in LEX8 range is 5 ADC units (0.17 MeV).
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