ACD tile events with only one adc
above zero-suppress threshold
Larry Wai
January 13, 2006
Review (Oct.21 presentation)
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I&T ACD Triggered Op run 134001103
No Tracker or Calorimeter
Typical events have zero or at most a
few tiles w/ one adc hit
For events with >10 tiles hit, two classes
of events emerge:
1. Events with a few tiles w/ one adc hit
2. Events with most tiles w/ one adc hit
“big event”
• Evt # 337442
• 74 tiles hit
• 7 tiles w/ single adc
hit
Another “large” event with many
single adc hit tiles
• Evt # 3462
• 20 tiles hit
• 15 tiles w/ single adc
hit
Question of the day
• Are the events w/ >10 tiles and mostly w/
one adc hit real physics events or bursts of
noise?
• Check this by looking at ACD triggered
events w/ TKR; i.e. for bursts of noise, we
should see no hits in the TKR, whereas for
“real” large events we should see lots of
hits in the TKR
Run info
• I&T ACD Triggered Op run 135005097
(Dec.30)
• Coincidence regions are top-side (x4),
opposite sides (x2), adjacent sides (x2)
• Has TKR and CAL on
Events w/ large numbers of double
adc hit tiles
Events w/ large numbers of single
adc hit tiles
questions
• Do the events w/ large numbers of single
adc hit tiles have a reconstructed track?
• What is the probability of having N-tiles
with single adc hits given noise hit rates?
(we still need to calibrate zero suppress
thresholds)