Transcript ppt

GLAST LAT Project
LAT Instrument Analysis Meeting– Jan 27, 2006
GLAST Large Area Telescope:
Gamma-ray Large
Area Space
Telescope
TKR 16-Tower Data Update
Hiro Tajima (SLAC)
TKR
[email protected]
650-926-3035
Hiro Tajima, TKR 16-tower data update
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GLAST LAT Project
LAT Instrument Analysis Meeting– Jan 27, 2006
TkrTrack::getScatter() Issue
• TkrTrack::getScatter() variable is wildly different with 16-tower
data from any previous data.
– Cause is not understood yet.
– Bill suggested to look at initialEnergy.
• Looks different for unknown reason.
• Does this explain the difference of getScatter()?
8-tower data
16-tower data
Hiro Tajima, TKR 16-tower data update
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GLAST LAT Project
LAT Instrument Analysis Meeting– Jan 27, 2006
TOT Saturated Events
•
SVAC reported much more TOT saturated events in B/2 runs.
– Gem::getDeltaEventTime() for TOT saturated events is mostly less
than 1000 ticks. (<50 µs)
– TOT saturated GTRC has long TOT (>30 µs) in the previous event.
– TOT is set to 255 when next TACK is issued during TOT
conversion.
– B/30 has less TOT saturation due to long dead time. (>50 µs)
Previous event TOT saturated event
All events
TOT saturated events
Hiro Tajima, TKR 16-tower data update
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GLAST LAT Project
LAT Instrument Analysis Meeting– Jan 27, 2006
Bad Channel Trend
• No big changed observed for 16-tower data.
Bad Channel Trend
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TkrFMA
TkrFMB
TkrFM1
TkrFM2
TkrFM3
TkrFM5
TkrFM4
TkrFM6
TkrFM7
TkrFM9
TkrFM10
TkrFM11
TkrFM12
TkrFM13
TkrFM14
TkrFM15
Bad channel increase
16
12
8
4
0
-4
2TWR
4TWR
6TWR
8TWR
16TWR
Test phase
Hiro Tajima, TKR 16-tower data update
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