User name Roedelbronn
Log entry time 22:22:15 on January14,2002
Entry number 80330
keyword=Veto count rate
I looked at the veto counting rates for several runs. Counting rate was calculated using the accidental veto hits from a 200 channel band in that detector's TDC (all hits filling the histogram) Below are two sets of plots. The first is for run 1488, the second for run 1509. These runs were done at essentially the same conditions except approximately 6 cm of plastic was placed in front of the veto detectors prior to run 1509. It covered a band approximately 35 cm wide and across the width of the detectors, centered a little below the detector center. Note that the shielding had a noticable effect across the board. The low dips in the second plot for the horizontal detector correspond to the area covered by the shielding material.