GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 1 Comprehensive review of CAL calibrations Gamma-ray.

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 1 Comprehensive review of CAL calibrations Gamma-ray Large Area Space Telescope 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

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 2 Trending CAL performance parameters : an introduction 1/5 Let’s start with an example: pedestals Define parameters –pedestal positions –pedestal widths Define phases –pre-ship (“Pshp”) –post-ship (“SLAC”) –8 towers in GRID (“8T”) 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!

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 3 Trending CAL performance parameters : an introduction 2/5 1 face distribution raw plots 4 energy ranges 48 channels Pedestal widthsPedestal positions

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 4 Trending CAL performance parameters : an introduction 3/5 1 channel 1 energy range history plots 3 phases Variation (phase 0 ALWAYS 0) Pedestal positions Pedestal widths Change of TPS before inserting in the GRID

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 5 Trending CAL performance parameters : an introduction 4/5 1 face history plots 4 energy ranges Mean+-RMS, MIN and MAX 48 channels RMS, 0.5(MAX – MIN) Pedestal widthsPedestal positions

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 6 Trending CAL performance parameters : an introduction 5/5 summary plots RMS and 0.5(MAX – MIN), summed over all last histograms Sometimes expressed in percentage Change of TPS before inserting in the GRID

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 7 Trending CAL performance parameters from CPT’s 1/15 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

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 8 Trending CAL performance parameters from CPT’s 2/15 T00-FM104

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 16 Trending CAL performance parameters from CPT’s 10/15 T12-FM110 Lack of statistics ?

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 17 Trending CAL performance parameters from CPT’s 11/15 T00-FM104T04-FM105

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 21 Trending CAL performance parameters from CPT’s 15/15 Check the fit for these guys…

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 22 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

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 23 Trending CAL performance parameters from calibration files 2/16 T00-FM104

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 30 Trending CAL performance parameters from calibration files 9/16 T00-FM104 T01-FM103 Energy gains are larger (and stable) in the GRID

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 38 Mapping CAL crystals and energy response Use TKR tacks (Tkr1XYZDir) and CAL tracks (CalXYZDir) Select events (% is given for 2 towers) –CalZDir<1 (90%) –TkrNumTracks==1 (80%) –>6 hits above 2 MeV in at least one tower (25%) 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%)

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 39 Comparing TKR and CAL extrapolated tracks start of track end of track multiple scattering ?? From Benoit’s note (4GeV) RMS of difference in lateral position RMS of difference in longitudinal position E < 2 GeVE > 3.5 GeV 0.8 mm 1.4 mm

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 40 Comparing TKR extrapolated track with MC truth E < 2 GeV E > 3.5 GeV 0 mm 2 mm 0.3 mm 0.9 mm multiple scattering effect is dominant RMS of difference in lateral position RMS of difference in longitudinal position E < 2 GeV E > 3.5 GeV

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 41 Comparing CAL extrapolated track with MC truth RMS of difference in lateral position RMS of difference in longitudinal position 14 mm 0 mm TKR-CAL discrepancy is not due to multiple scattering in CAL E < 2 GeV E > 3.5 GeV E < 2 GeV

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 42 Mapping CAL crystals using TKR extrapolated tracks Divide each crystal in 9 (3mm) * 54 (6mm) bins Map of hits per binMap of mean energy per bin

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 43 Mapping CAL crystals using TKR extrapolated tracks Map of hits per bin 50 140 00 MeV 20 MeV

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 44 Crystal longitudinal energy response profile (tower0, layer0) 2 towers6 towers -10 % +10 %

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 45 Distribution of MPV’s – 2 and 6 towers 2 towers: = 11.25 +- 0.007 MeV 6 towers: = 11.58 +- 0.004 MeV

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 46 Distribution of MPV’s – 4 towers 4 towers: old calibration 2 peaks at 10.8 and 11.2 MeV 4 towers: new calibration = 11.41 +- 0.05 MeV

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 47 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 Conclusions

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 1 Comprehensive review of CAL calibrations Gamma-ray.

Similar presentations

Presentation on theme: "GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 1 Comprehensive review of CAL calibrations Gamma-ray."— Presentation transcript:

Similar presentations

About project

Feedback

Log in

Auth with social network:

GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 1 Comprehensive review of CAL calibrations Gamma-ray.

Similar presentations

Presentation on theme: "GLAST LAT Project Instrument Analysis Workshop 5 – 05/08/29 F. Piron & E. Nuss (IN2P3/LPTA – Montpellier) 1 Comprehensive review of CAL calibrations Gamma-ray."— Presentation transcript:

Similar presentations

About project

Feedback