1. HyCal reconstruction: current situation current situation and future tasks. V. Mochalov, IHEP (Protvino)

2. V. Mochalov. HyCal Status 2 July 29, 2005 Part I. Calibration issues HyCal reconstruction code HyCal reconstruction code Cluster reconstruction Cluster reconstruction Timing in HyCal Timing in HyCal HyCal Energy Calibration HyCal Energy Calibration Snake Calibration and short term stability Snake Calibration and short term stability Physics Calibration and long term stability Physics Calibration and long term stability HyCal position reconstruction HyCal position reconstruction Methods Methods Investigations Investigations

3. V. Mochalov. HyCal Status 3 July 29, 2005 Part II. Physics and planning Physics Physics Status Status Methods Methods Detector stability Detector stability Required checks of the detector Required checks of the detector Required input information from other sources Required input information from other sources Calculation efficiencies Calculation efficiencies Planning Planning

4. V. Mochalov. HyCal Status 4 July 29, 2005 Cluster code done Methods incorporated to the program for Cluster Methods incorporated to the program for Cluster 3 different methods of coordinate reconstruction – I. Larin (see Kelly talk) 3 different methods of coordinate reconstruction – I. Larin (see Kelly talk) Depth correction for coordinate reconstruction (photon shower) I. Larin Depth correction for coordinate reconstruction (photon shower) I. Larin Energy correction (from calibration) I.Larin Energy correction (from calibration) I.Larin Island algorithm Island algorithm Description of the glass shower shape Description of the glass shower shape Method to calculate shower chi^2 Method to calculate shower chi^2 Shower leakage outside detector Shower leakage outside detector

5. V. Mochalov. HyCal Status 5 July 29, 2005 Depth correction (Ilya)

6. V. Mochalov. HyCal Status 6 July 29, 2005 Energy correction (Ilya) Should be recalculated because of new tagger calibration. Should be recalculated because of new tagger calibration.

7. V. Mochalov. HyCal Status 7 July 29, 2005 Glass shower shape

8. V. Mochalov. HyCal Status 8 July 29, 2005 Cluster code to do. Cross-check of new cluster code (Dustin) Cross-check of new cluster code (Dustin) Check shower leakage outside (recomendations from soft. techn.) Check shower leakage outside (recomendations from soft. techn.) Introduce shower leakage inside Introduce shower leakage inside Shower shape for PWO required Shower shape for PWO required Study energy and coordinate reconstruction in transition region Study energy and coordinate reconstruction in transition region Correction on beam angle and position Correction on beam angle and position Introduce leakage inside “holes” Introduce leakage inside “holes” Introduce “electron depth (and energy?) correction” Introduce “electron depth (and energy?) correction” Overlapping showers algorithm Overlapping showers algorithm

9. V. Mochalov. HyCal Status 9 July 29, 2005 Timing in HyCal done Package to reconstruct time for HyCal triggers was developed (Ilya, Dustin and Vasiliy) Package to reconstruct time for HyCal triggers was developed (Ilya, Dustin and Vasiliy) Time calibration (Ilya and Dustin) Time calibration (Ilya and Dustin) Functions to search Functions to search Horizontal and vertical coincidence Horizontal and vertical coincidence Clusters with the same time Clusters with the same time Coincidence between Cluster and tagger Coincidence between Cluster and tagger

10. V. Mochalov. HyCal Status 10 July 29, 2005 Pair hits in PWO

11. V. Mochalov. HyCal Status 11 July 29, 2005 Timing calibration accuracy Efficiency is small: Efficiency is small:

12. V. Mochalov. HyCal Status 12 July 29, 2005 Timing links to do Cross-check code Cross-check code Study and define all required cuts Study and define all required cuts Study efficiency of the timing reconstruction (and time offsets??) using snake calibration data Study efficiency of the timing reconstruction (and time offsets??) using snake calibration data

13. V. Mochalov. HyCal Status 13 July 29, 2005 Snake calibration status Was done by Ilya for energy about 2 GeV Was done by Ilya for energy about 2 GeV Energy resolution about 1.7% (except ROC4) for PWO and 4% for glass. Energy resolution about 1.7% (except ROC4) for PWO and 4% for glass. Close to expected Close to expected But should be repeated But should be repeated

14. V. Mochalov. HyCal Status 14 July 29, 2005 Snake calibration to do Repeat calibration due to Repeat calibration due to Take into account actual photon energy: Take into account actual photon energy: New tagger calibration constants New tagger calibration constants electron beam energy (Hall C) electron beam energy (Hall C) Take into account leakage Take into account leakage Use all energy range for calibration Use all energy range for calibration Repeat energy dependence Repeat energy dependence Final study of energy resolution using calibration data, including dependence on beam energy, individual for channels... (prepare all required for publication). Final study of energy resolution using calibration data, including dependence on beam energy, individual for channels... (prepare all required for publication).

15. V. Mochalov. HyCal Status 15 July 29, 2005 Short time stability Left – Ilya found the effect on LMS Left – Ilya found the effect on LMS Possible pile-up and rate dependence effect (Kelly) Possible pile-up and rate dependence effect (Kelly) LMS dependence (Dustin) LMS dependence (Dustin)

16. V. Mochalov. HyCal Status 16 July 29, 2005 Long term stability Comparison of the first and second snake calibrations (electron and LMS) – Dustin Comparison of the first and second snake calibrations (electron and LMS) – Dustin LMS correction LMS correction Compton calibration data (Elena) Compton calibration data (Elena) Single arm Compton for production runs Single arm Compton for production runs Pair production Pair production pi-0 data pi-0 data

17. V. Mochalov. HyCal Status 17 July 29, 2005 Compton conclusions Possibility to use calibration (resolution is close to 1.7/sqrt(E)%) Possibility to use calibration (resolution is close to 1.7/sqrt(E)%) Clearly seen changes on time Clearly seen changes on time Difference between photon and electron (need to check using pair production) Difference between photon and electron (need to check using pair production) LMS is correlated, accuracy should be improved LMS is correlated, accuracy should be improved Final tagger reconstruction is required to finish Final tagger reconstruction is required to finish Beam position and angle is required to finish Beam position and angle is required to finish Need to study possibility of single-arm Compton Need to study possibility of single-arm Compton Pair production calibration is very important Pair production calibration is very important

18. V. Mochalov. HyCal Status 18 July 29, 2005 Position reconstruction 3 different methods were introduced. 3 different methods were introduced. Compton data showed the best result for logarithm method. Compton data showed the best result for logarithm method. Kelly investigated 3 different methods for calibration data Kelly investigated 3 different methods for calibration data Depth correction is done for photon – the same procedure is required for electrons Depth correction is done for photon – the same procedure is required for electrons Transition region study next month Transition region study next month

19. V. Mochalov. HyCal Status 19 July 29, 2005 Physics status First version of skim files for pi0 is ready (3.1M pi0's) First version of skim files for pi0 is ready (3.1M pi0's) Compton skim files: 2-nd versions is preparing Compton skim files: 2-nd versions is preparing New versions will be created when final bank structure will be prepared. New versions will be created when final bank structure will be prepared. Methods for correct mass and energy are prepared by Ilya Methods for correct mass and energy are prepared by Ilya Methods to calculate number of pi0 are prepared by Ilya Methods to calculate number of pi0 are prepared by Ilya

20. V. Mochalov. HyCal Status 20 July 29, 2005 Energy and mass constraint methods (Ilya)

21. V. Mochalov. HyCal Status 21 July 29, 2005 pi-0 distributions (Ilya).

22. V. Mochalov. HyCal Status 22 July 29, 2005 Detector stability and required checks DAQ errors and it's recovery DAQ errors and it's recovery Sparcification cut investigation (Nick's talk) Sparcification cut investigation (Nick's talk) Bad/noisy channels (ADC's) Bad/noisy channels (ADC's) Trigger group stability Trigger group stability Trigger threshold and the stability Trigger threshold and the stability

23. V. Mochalov. HyCal Status 23 July 29, 2005 Information required from other sources For calibration: For calibration: Actual electron beam energy-> tagger energy Actual electron beam energy-> tagger energy For physics calibration and physics For physics calibration and physics Beam position on the detector Beam position on the detector Beam position (and angle) on the target Beam position (and angle) on the target Information not used now: Information not used now: Slow control, including temperature and humidity Slow control, including temperature and humidity

24. V. Mochalov. HyCal Status 24 July 29, 2005 Efficiency of the reconstruction Trigger efficiency for whole detector and each strip/quadrant on energy Trigger efficiency for whole detector and each strip/quadrant on energy Influence of the different cuts on reconstruction efficiency: Influence of the different cuts on reconstruction efficiency: Timing cuts; Timing cuts; Cluster energy cuts; Cluster energy cuts; Elasticity cuts; Elasticity cuts;......

25. V. Mochalov. HyCal Status 25 July 29, 2005 Planning: Snake Calibration Preparation for final calibration: Preparation for final calibration: Finish tagger reconstruction – include beam energy (Eric?) Finish tagger reconstruction – include beam energy (Eric?) Software (Leakage of the cluster): Software (Leakage of the cluster): Prepare shower shape for PWO (Vasiliy) Prepare shower shape for PWO (Vasiliy) Investigate leakage procedure (see recommendations from software technical meeting). Investigate leakage procedure (see recommendations from software technical meeting). Add shower leakage inside calorimeter (Vasiliy) Add shower leakage inside calorimeter (Vasiliy) Add shower leakage to holes (Vasiliy) Add shower leakage to holes (Vasiliy) Find bad/noisy channels and describe them as holes (who?) Find bad/noisy channels and describe them as holes (who?) Finish sparcification cuts (Dustin?) Finish sparcification cuts (Dustin?)

26. V. Mochalov. HyCal Status 26 July 29, 2005 Planning: Snake Calibration (ctd) Software (timing in the calorimeter) Software (timing in the calorimeter) Check time calibration for strips (quadrants) Check time calibration for strips (quadrants) Study and select time windows for cluster Study and select time windows for cluster Run final snake energy calibration for all energies Run final snake energy calibration for all energies repeat energy dependence for each channel (Vasiliy+?) repeat energy dependence for each channel (Vasiliy+?) Prepare Figures for publication concerning energy resolution of the detector (Vasiliy) Prepare Figures for publication concerning energy resolution of the detector (Vasiliy) LMS calibration (?) LMS calibration (?) Study also the timing and trigger inefficiencies(?) Study also the timing and trigger inefficiencies(?)

27. V. Mochalov. HyCal Status 27 July 29, 2005 Compton calibration (Elena) Preparations for final Compton calibration procedure: Preparations for final Compton calibration procedure: Beam position and angle required !!! Beam position and angle required !!! Final tagger energy reconstruction Final tagger energy reconstruction Software: add matrix inversion method. Software: add matrix inversion method. Compton calibration coefficients for Compton data: Compton calibration coefficients for Compton data: Comparison with snake calibration Comparison with snake calibration Comparison of the LMS and Compton calibration Comparison of the LMS and Compton calibration Compare different coordinate reconstruction methods Compare different coordinate reconstruction methods Single arm Compton Calibration on Compton (and production!?) runs Single arm Compton Calibration on Compton (and production!?) runs Pair production calibration is required (who ?!!! ) Pair production calibration is required (who ?!!! )

28. V. Mochalov. HyCal Status 28 July 29, 2005 Physics planning Software: Software: Finish coordinate reconstruction procedure Finish coordinate reconstruction procedure Transition region coordinate Transition region coordinate DAQ errors DAQ errors Study all possible inefficiencies in reconstruction Study all possible inefficiencies in reconstruction Compton cross-section (compare with theory) Compton cross-section (compare with theory) Veto inefficiency Veto inefficiency Single arm compton Single arm compton Pair production cross-section (compare with theory) Pair production cross-section (compare with theory)

29. V. Mochalov. HyCal Status 29 July 29, 2005 If compton and pair production are compatible with theory we are ready for π 0 data.