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In November 96, John and I did laser scans of the beamtest silicon+FEE.
This is run 849x.
The laser was scanned over all 32 active channels, in 10 micron steps. At each
step, the laser was fired 30 times. The laser settings were xxV; roughly, this
translates to xx (7) mips. The silicon bias was at 30xxV.
Note that this was detector #2, which in our DAQ corresponds to channels
33-64.
John also wrote a note on the laser scan results.
Below is shown, for channels 53-56, the following:
You can see that the cut fishes out the signal for the four shown channels. Channel 53 is noisier than 54-56. This is clear in width of the baseline in the left plot, and in the signal distribution on the top right.
Some more features can be seen in some other channels; look at this postscript file of all channels. Some channels are textbook examples, such as the ones on page xx (ch 54-56), and some are clearly dead (ch 34, 35, 39, 40, 42). Some channels seem to have a lot of noise, but the signal can be pulled out nicely (ch 33-40, 42, 53, 57, 61)
On the next page, the means and widths of the gaussians are plotted for each channel.