CDC Pedestal Studies
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Pedestal Subtraction
Based on cosmic ray data with BCAL trigger Look for events with the following signature in the CDC:
The first test was done by using the region (blue) to determine a pedestal and the region I (red) to determine an Integral and then subtract the proper pedestal from the Intergral as follows: where is the number of samples used to calculate the pedestal and 80 is the number of samples in the Integral I. In the case of no signal the the distribution D is expected to be around zero with a sigma that reflects the resolution and depends on the number samples used in determining the pedestal. As an example the distribution with 4 samples in the pedestal calculation looks like this:
mean F | sigma F | mean I | sigma I | |
---|---|---|---|---|
4 | 102.2 | 1293 | 96.5 | 1276 |
16 | 119.0 | 1121 | 163.4 | 1120 |
20 | 121.1 | 1080 | 145.1 | 1080 |
32 | 102.4 | 984 | 159.0 | 978 |
64 | 40.9 | 680 | 84.6 | 685 |