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 1 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 2 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 3 GLAST LAT Project LAT Instrument Analysis Meeting– Jan 27, 2006 Bad Channel Trend • No big changed observed for 16-tower data. Bad Channel Trend 20 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 4