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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:

• On the left, the signal height (in ADC channels) as a function of the laser position (on a xx-mm scale). The pair of vertical lines are calculated from the laser position, and predict where the signal should show up. In this plot, the width of this window is +-10 steps.
• On the right, the top plot of each channel shows the ADC distribution over the entire scan.
• the bottom of the right-hand pair shows the ADC distribution inside the narrow 'signal window' marked in the plot on the left. To this signal, I fit a gaussian, excluding counts less than zero.

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.