1. GLAST LAT Project Software vrvs meeting X. Chen 1 GLAST LAT Project Software vrvs meeting X. Chen 1 Analyses of Muon Calibration Data Xin Chen

2. GLAST LAT Project Software vrvs meeting X. Chen 2 GLAST LAT Project Software vrvs meeting X. Chen 2 Outline Use Sasha’s scripts to produce calibration constants from muon calibration data –Study time dependence of the constants Use Gleam to read in the constants and reconstruct the data –Study cosmic ray data and VDG data with EM placed horizontally Goal: exercise the whole data analyses chain and verify results make sense

3. GLAST LAT Project Software vrvs meeting X. Chen 3 GLAST LAT Project Software vrvs meeting X. Chen 3 EM Data used in analyses DateRun typeTrigger Sep 27 – Oct 1, 2003CosmicCAL_LO Oct 2 – Oct 5, 2003CosmicExternal Oct 6 – Oct 8, 2003VDG3 in a row / CAL_LO Oct 9 – Oct 12, 2003CosmicExternal From Sep 28 th to Oct 12 th, two runs (~ 4 hours) were used to produce calibration Constants for the calorimeter

4. GLAST LAT Project Software vrvs meeting X. Chen 4 GLAST LAT Project Software vrvs meeting X. Chen 4 Raw ADC distribution for layer 0, column 6, end 0, range 0 Data taken on Sep 27 th, 2003 Pedestal Muon peak

5. GLAST LAT Project Software vrvs meeting X. Chen 5 GLAST LAT Project Software vrvs meeting X. Chen 5 Light asymmetry = Log ( ADC(pos) / ADC(neg) ) Slope is the calibrated attenuation length

6. GLAST LAT Project Software vrvs meeting X. Chen 6 GLAST LAT Project Software vrvs meeting X. Chen 6 Muon peak distribution for layer 0, column 6, end 0, range 0 Data taken on Sep 27 th, 2003 1 MIP = 12.3 MeV

7. GLAST LAT Project Software vrvs meeting X. Chen 7 GLAST LAT Project Software vrvs meeting X. Chen 7 Changes in pedestal 2*(Ped 928 -Ped 929 )/(Ped 928 +Ped 929 ) 2*(Ped 928 -Ped 1001 )/(Ped 928 +Ped 1001 ) 2*(Ped 928 -Ped 1005 )/(Ped 928 +Ped 1005 ) 2*(Ped 928 -Ped 1012 )/(Ped 928 +Ped 1012 ) Pedestal change No of channels

8. GLAST LAT Project Software vrvs meeting X. Chen 8 GLAST LAT Project Software vrvs meeting X. Chen 8 Changes in light attenuation length No of channels Slope change 2*(Slope 928 -Slope 929 )/(Slope 928 +Slope 929 ) 2*(Slope 928 -Slope 1001 )/(Slope 928 +Slope 1001 ) 2*(Slope 928 -Slope 1005 )/(Slope 928 +Slope 1005 ) 2*(Slope 928 -Slope 1012 )/(Slope 928 +Slope 1012 )

9. GLAST LAT Project Software vrvs meeting X. Chen 9 GLAST LAT Project Software vrvs meeting X. Chen 9 Changes in muon peak No of channels Peak change 2*(Peak 928 -Peak 929 )/(Peak 928 +Peak 929 ) 2*(Peak 928 -Peak 1001 )/(Peak 928 +Peak 1001 ) 2*(Peak 928 -Peak 1005 )/(Peak 928 +Peak 1005 ) 2*(Peak 928 -Peak 1012 )/(Peak 928 +Peak 1012 )

10. GLAST LAT Project Software vrvs meeting X. Chen 10 GLAST LAT Project Software vrvs meeting X. Chen 10 Time Dependence Estimate Within 16 days: –Changes in pedestal are less than 0.8% ~ 10000 events used in the fitting –Changes in attenuation length are less than 5% ~ 900 events used in the fitting –Changes in muon peak are less than 4% ~ 500 events used in the fitting No significant time dependence. May need to process more events to achieve better accuracy –Is this desirable considering the efforts?

11. GLAST LAT Project Software vrvs meeting X. Chen 11 GLAST LAT Project Software vrvs meeting X. Chen 11 VDG photons on EM CALTKR 66% 17.6 MeV, 34% 14.6 MeV Cosmic Background

12. GLAST LAT Project Software vrvs meeting X. Chen 12 GLAST LAT Project Software vrvs meeting X. Chen 12 Raw ADC distribution for all crystals No of entries Raw ADC counts pedestal muon Cosmic: ebf031009105206 Without calibrations

13. GLAST LAT Project Software vrvs meeting X. Chen 13 GLAST LAT Project Software vrvs meeting X. Chen 13 Calibrated energy for all crystals, zDir < -0.9 VDG+Cosmic: ebf031007191651 Cosmic: ebf031009105206 Pedestal Muon peak VDG events Two runs are normalized by the run time (MeV)

14. GLAST LAT Project Software vrvs meeting X. Chen 14 GLAST LAT Project Software vrvs meeting X. Chen 14 Calculate total energy deposited in CAL Require at least 1 crystal has deposited energy > 4MeV –Remove almost all of noises Sum only the largest 12 deposited energies in crystals Only use events going along the z axis of the tracker (zDir < -0.9) to avoid path length dependence

15. GLAST LAT Project Software vrvs meeting X. Chen 15 GLAST LAT Project Software vrvs meeting X. Chen 15 Energy spectrum VDG+Cosmic: ebf031007191651 Cosmic: ebf031009105206 Two runs are normalized by the run time calEnergy*(-zDir) (MeV) Number of events “Photon” Muon

16. GLAST LAT Project Software vrvs meeting X. Chen 16 GLAST LAT Project Software vrvs meeting X. Chen 16 VDG photons on EM CAL TKR 66% 17.6 MeV, 34% 14.6 MeV Cosmic Background

17. GLAST LAT Project Software vrvs meeting X. Chen 17 GLAST LAT Project Software vrvs meeting X. Chen 17 Energy spectrum VDG+Cosmic: ebf031008000405 calEnergy (MeV) Number of events EM is vertically placed, photons come from side of CAL Photon Muon

18. GLAST LAT Project Software vrvs meeting X. Chen 18 GLAST LAT Project Software vrvs meeting X. Chen 18 Conclusion There does not seem to be any significant time dependences of the calibration constants for CAL With calibration constants, energy spectra of VDG and cosmic signals make senses The full data analysis chain (produce constants, read in constants, reconstruction) has been exercised. Some code modifications are necessary. –Next Wednesday vrvs meeting ?