1. M.D. Nov 27th 2002M0' workshop1 M0’ linearity study  Contents : Electronic injection Laser injection Beam injection Conclusion

2. M.D. Nov 27th 2002M0' workshop2 Monitoring system description Absolute linearity study of PN readout electronics Relative linearity study of APD readout electronics with respect to PN diodes Beam : Consistency check of the method

3. M.D. Nov 27th 2002M0' workshop3 PN linearity with test pulse  Able to measure absolute non-linearity on PN electronics Look at residuals

4. M.D. Nov 27th 2002M0' workshop4 APD study : Pedestal corrections  Remarks on pedestals : Variation with laser intensity  100 crystals fired at the same time ! BUT :  Pedestals different for Fixed G33 and Free G33 !  Hidden free gains (G9, G5 and G1) pedestals inaccessible ! Affect energy measurement !  Laser in fixed and free gain  Beam in free gain  Use dynamic pedestals XT1142

5. M.D. Nov 27th 2002M0' workshop5 FPPA non-linearity after PN correction  Non-linearities less pronounced in G33 than previously found in september Effect of dynamic pedestals XT1142

6. M.D. Nov 27th 2002M0' workshop6 Beam injection  Ingredients : Energy computation  Dynamic pedestals (not very useful : fixed gain)  Crystal intercalibration @ 120 GeV/c, @G33  G33/G9 intercalibration from Laser runs  To be refined due to change of fppa shaping time with amplitude (G9)  disentangle laser pulse width and fppa shaping effects  Use experimental pulse shapes Two energy scan :  2002/08/07 : 20 – 35 – 50 – 80 – 120 – 150 – 180 GeV/c  2002/08/23 : 20 – 30 – 50 – 80 – 120 – 150 – 180 –200 – 250 – 280 GeV/c Look at crystal 1142 & 1144 For single crystal analysis :  2x2 mm at maximum energy deposition

7. M.D. Nov 27th 2002M0' workshop7 Beam injection  Location of maximum energy deposition : Log dependence with energy Different for X and Y Check in MC (A. Givernaud)  OK

8. M.D. Nov 27th 2002M0' workshop8 Linearity results with beam  Without linearity corrections : 2002/08/07 XT1142XT1144 Suspicious runs … Wrong Xtal ? Calibration change by 6/1000 between 2002/08/07 and 2002/08/23 !

9. M.D. Nov 27th 2002M0' workshop9 Linearity results with beam  With linearity corrections : XT1142XT1144 No laser data at this energy for this crystal

10. M.D. Nov 27th 2002M0' workshop10 Resolution with electron  Single crystal (  1 ) : ~250 MeV noise XT1142 2002/08/07 2002/08/23 2002/08/07 2002/08/23 XT1144

11. M.D. Nov 27th 2002M0' workshop11 Resolution with electron  Sum of 5 crystals (  5 ) : ~1250 MeV noise XT1142XT1144 2002/08/07 2002/08/23 2002/08/07 2002/08/23

12. M.D. Nov 27th 2002M0' workshop12 Resolution with electron  Sum of 9 crystals (  9 ) : ~2000 MeV noise XT1142XT1144 2002/08/07 2002/08/23 2002/08/07 2002/08/23

13. M.D. Nov 27th 2002M0' workshop13 Look at noise correlation  Correlation : About 50 % on the whole matrix  Correction : Remove 5x5 matrix around fired crystal Compute sample average on remaining 74 crystals Correct all samples event by event Redo energy reconstruction 1142

14. M.D. Nov 27th 2002M0' workshop14 Resolution with electron after decorrelation  Single crystal (  1 ) : ~180 MeV noise (was 250) XT1142 2002/08/07 2002/08/23 2002/08/07 2002/08/23 XT1144

15. M.D. Nov 27th 2002M0' workshop15 Resolution with electron after decorrelation  Sum of 5 crystals (  5 ) : ~750 MeV noise (was 1250) XT1142XT1144 2002/08/07 2002/08/23 2002/08/07 2002/08/23

16. M.D. Nov 27th 2002M0' workshop16 Resolution with electron after decorrelation  Sum of 9 crystals (  9 ) : ~1000 MeV noise (was 2000) XT1142XT1144 2002/08/07 2002/08/23 2002/08/07 2002/08/23 Steps not compatible with g33/g9 noise ratio

17. M.D. Nov 27th 2002M0' workshop17 Conclusions and to-do list  Linearity : Linearity measurement with laser in good agreement with beam results for E > 50 GeV Need to understand discrepancy for lower energy  Preliminary results on MC shows lower shower containment in single crystal for low energy particles  Effect of material in front of M0’ ?  Beam calibration ?  Others ?  Noise : Simple decorrelation algorithm improve resolution for about a factor of 2. Need to understand G33/G9 noise step  Extra contribution ? Try  5 and  9 in free gain mode  Calibration : Understand drift with time !