I discovered that 3 cables going to ADCs (TOF: left bottom, right top and bottom)
have been shifted 1 pin up. As a result, the information read was shifted, and, for
instance, what we believed was atl3b, was actually atl4b.
I replugged the cables into ADC correctly, but it still needs to be checked when
we start data taking again.
Here is the way to check it.
In order to check if top and bottom ADCs correspond to each other, one can build
a plot adctop versus adcbottom, and see a clear correlation betwwen the two.
It would not work for the problem in right side (since BOTH cables were shifted
by 1 pin), but one can also check the correlation between ADCs and TDCs. The clearest
way to do it to plot the coordinate measured by TDCs and ADCs in the same scintillator.
For instance, build Ytdcleft5 = (ttl5t-ttl5b) versus
Yadcleft5 = (atl5t-atl5b)/(atl5t+atl5b)*1000
and one must see a clear correlation as well.
It is VERY easy to plug these cables incorrectly. I didn't check other
cables (Cherenkovs, and none of TDCs), perhaps it needs to be done.
Genya
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