(P. Decowski, A. Olszewski, H. Pernegger, P. Sarin)
Pedestal and noise levels in runs of the Test Beam '98 have been investigated with the current implementation of the raw signal processing procedure in Phat. Several runs have been chosen at random, and comparison of the changes in pedestal and noise levels during a single run and between the runs have been calculated. Below, a review of histograms for variation in pedestals and noise is given. Pedestal changes are scaled by their RMS spread calculated in one of the samples while noise changes are given in pure ADC units.
In the analysis of changes during a single run, five runs: 010, 034, 065, 069 and 087 have been used with a gap of 5000 events, two runs have been used with a gap of 30000 events, and finaly four pairs of runs: 010-069, 034-069, 065-069 and 087-069 have been compared between themselves. Below, there are two types of plots shown. On the first one a distribution of pedestal or noise changes is given for each of the channels in a given string, on the second type of the plot a histogram of these changes is shown.
Written by Andrzej Olszewski on 03/31/99