Transcript ppt

Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Comprehensive review of
CAL calibrations
Gamma-ray Large Area
Space Telescope
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
•
Trending CAL performance parameters as
a function of LAT assembly phase:
– from Comprehensive Performance
Tests
– from calibration files (calibGenCal)
•
Mapping CAL crystals and energy
response
•
Conclusions
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GLAST LAT Project
Instrument Analysis Workshop 5 – 05/08/29
Trending CAL performance parameters : an introduction 1/5
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Let’s start with an example: pedestals
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Define parameters
– pedestal positions
– pedestal widths
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Define phases
– pre-ship (“Pshp”)
– post-ship (“SLAC”)
– 8 towers in GRID (“8T”)
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Trend parameters in 3 steps
– Raw plots: plot raw values for each channel
– History plots: plot parameters variation w.r.t. first phase
(“Reference=Pshp”)
– Summary plots: to have a first quick look
•
Store plots in 1 pdf file per CAL module (147 pages for calibGenCal
trending, 133 for CPTs !!) and scan it!
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters : an introduction 2/5
raw plots
1 face
distribution
4 energy
ranges
48 channels
Pedestal positions
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
Pedestal widths
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters : an introduction 3/5
history plots
1 channel
1 energy
range
3 phases
Change of TPS before
inserting in the GRID
Variation (phase 0
ALWAYS 0)
Pedestal positions
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
Pedestal widths
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters : an introduction 4/5
history plots
1 face
4 energy
ranges
Mean+-RMS,
RMS,
MIN and MAX
0.5(MAX – MIN)
48 channels
Pedestal positions
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
Pedestal widths
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters : an introduction 5/5
summary plots
Change of TPS before
inserting in the GRID
RMS and 0.5(MAX – MIN), summed over all last histograms
Sometimes expressed in percentage
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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GLAST LAT Project
Instrument Analysis Workshop 5 – 05/08/29
Trending CAL performance parameters from CPT’s 1/15
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What do we trend ?
– Compute pedestals: we trend position and width
– Check optical response (with muons):
• a test for changes in the PDA (photo-diode assembly) optical
bond quality is made from the ratio of LE or HE diode signals
• we trend LE+/LE-, LE+/HE+ and LE-/HE– Determine and trend optimal charge injection time delay (TACK
DELAY) under timed readout
– Calibrate electronic gains (with CI):
• we trend the lowest and highest relative gains (w.r.t. nominal
gains)
• these gains are chosen because any drift from the nominal
value would be most greatly amplified
– Determine front-end integral non-linearity and noise (with CI): we
trend noise, non-linearity (deviation from linear fit in %) and
DAC2ADC slope
– Characterize FLE, FHE, LAC and ULD DAC settings (with CI): we
trend the coarse range DAC2ADC slopes
•
Which phases ? Pre-ship, Post-ship, 8T
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from CPT’s 2/15
T00-FM104
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from CPT’s 3/15
T04-FM105
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from CPT’s 4/15
T01-FM103
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from CPT’s 5/15
T05-FM102
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from CPT’s 6/15
T08-FM107
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from CPT’s 7/15
T09-FM106
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from CPT’s 8/15
T12-FM110
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from CPT’s 9/15
T13-FM108
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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GLAST LAT Project
Instrument Analysis Workshop 5 – 05/08/29
Trending CAL performance parameters from CPT’s 10/15
T12-FM110
•
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
Lack of
statistics ?
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from CPT’s 11/15
T00-FM104
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
T04-FM105
17
Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from CPT’s 12/15
T01-FM103
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
T05-FM102
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from CPT’s 13/15
T08-FM107
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
T09-FM106
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from CPT’s 14/15
T12-FM110
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
T13-FM108
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from CPT’s 15/15
Check the fit for these guys…
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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GLAST LAT Project
Instrument Analysis Workshop 5 – 05/08/29
Trending CAL performance parameters from calibration files 1/16
•
•
What do we trend ?
– Compute pedestals: we trend position and width
–
ADC response:
• fit DAC to (pedestal subtracted) ADC in a region away from
non-linearities
• we trend xing value and DAC2ADC slope
–
Characterize asymmetry functions for small (S) and large (L)
diodes:
• Compute left/right ratios (L/L, L/S, S/L or S/S) as a function of
log segment (except 2 segments at the log ends)
• fit a linear function (though not well suitable...)
• we trend xing value and slope
–
Energy calibration: we trend the small and large diode MeV per
DAC constant
Which phases ? Pre-ship, 6T, 8T
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from calibration files 2/16
T00-FM104
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from calibration files 3/16
T01-FM103
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from calibration files 4/16
T05-FM102
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from calibration files 5/16
T08-FM107
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from calibration files 6/16
T09-FM106
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from calibration files 7/16
T12-FM110
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from calibration files 8/16
T13-FM108
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from calibration files 9/16
T00-FM104
T01-FM103
Energy gains are larger
(and stable) in the GRID
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from calibration files 10/16
T00-FM104
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
31
Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from calibration files 11/16
T01-FM103
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
32
Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from calibration files 12/16
T05-FM102
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
33
Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from calibration files 13/16
T08-FM107
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
34
Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from calibration files 14/16
T09-FM106
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
35
Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from calibration files 15/16
T12-FM110
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Trending CAL performance parameters from calibration files 16/16
T13-FM108
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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GLAST LAT Project
Instrument Analysis Workshop 5 – 05/08/29
Mapping CAL crystals and energy response
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Use TKR tacks (Tkr1XYZDir) and CAL tracks (CalXYZDir)
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Select events (% is given for 2 towers)
– CalZDir<1 (90%)
– TkrNumTracks==1 (80%)
– >6 hits above 2 MeV in at least one tower (25%)
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Data set:
– MC: 2 tower surface muons (22%)
– Data (Merit and Svac tuples):
• 2T : B/2 + B/10 + B/13 = 20h20’ (18%)
• 4T :
B/10 + B/13 = 2h00’ (22%)
• 6T : B/2 + B/10 + B/13 = 20h00’ (24%)
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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GLAST LAT Project
Instrument Analysis Workshop 5 – 05/08/29
Comparing TKR and CAL extrapolated tracks
RMS of difference in
lateral position
E < 2 GeV
E > 3.5 GeV
multiple scattering
??
From Benoit’s note (4GeV)
start of track
end of track
RMS of difference in
longitudinal position
1.4 mm
0.8 mm
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Comparing TKR extrapolated track with MC truth
2 mm
RMS of difference in lateral
position
E < 2 GeV
E > 3.5 GeV
0 mm
RMS of difference in longitudinal
position
E < 2 GeV
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
0.3 mm
0.9 mm
E > 3.5 GeV
multiple scattering effect is dominant
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Comparing CAL extrapolated track with MC truth
14 mm
RMS of difference in lateral
position
E < 2 GeV
E > 3.5 GeV
0 mm
RMS of difference in longitudinal
position
E < 2 GeV
TKR-CAL
discrepancy
F. Piron & E. Nuss (IN2P3/LPTA
– Montpellier)
E > 3.5 GeV
is not due to multiple scattering in CAL
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GLAST LAT Project
Instrument Analysis Workshop 5 – 05/08/29
Mapping CAL crystals using TKR extrapolated tracks
Divide each crystal in 9 (3mm) * 54 (6mm) bins
Map of hits per bin
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
Map of mean energy per bin
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Instrument Analysis Workshop 5 – 05/08/29
GLAST LAT Project
Mapping CAL crystals using TKR extrapolated tracks
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20 MeV
0
0 MeV
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Map of hits per bin
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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GLAST LAT Project
Instrument Analysis Workshop 5 – 05/08/29
Crystal longitudinal energy response profile (tower0, layer0)
+10 %
-10 %
2 towers
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
6 towers
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GLAST LAT Project
Instrument Analysis Workshop 5 – 05/08/29
Distribution of MPV’s – 2 and 6 towers
2 towers:
<MPV> = 11.25 +- 0.007 MeV
6 towers:
<MPV> = 11.58 +- 0.004 MeV
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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GLAST LAT Project
Instrument Analysis Workshop 5 – 05/08/29
Distribution of MPV’s – 4 towers
4 towers: old calibration
2 peaks at 10.8 and 11.2 MeV
4 towers: new calibration
<MPV> = 11.41 +- 0.05 MeV
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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GLAST LAT Project
Instrument Analysis Workshop 5 – 05/08/29
Conclusions
•
Trending and crystal mapping show calibration is stable
– variations in pedestals and MeV/DAC related to change of
TEM power supply
– definition of some parameters has to be improved (e.g.
asymmetry slopes)
– Need for a better way to extract csv and calibration files from
database to extend the trending to other LAT assembly levels
•
To do:
– redo 2 tower calibration using muons from B10 runs and CI
from 8T (4T calibration already re-done this way)
– reprocess 2T data using this new calibration (4T already
available)
– calibrate flight gains using muon gain calibration + relative
gains
F. Piron & E. Nuss (IN2P3/LPTA – Montpellier)
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