Ecal Simulation Status & Plans Brian Heltsley Simulation Mtg 26 Apr 2010

1. Ecal Simulation Status & Plans Brian Heltsley Simulation Mtg 26 Apr 2010 B. Heltsley Simulation Mtg - 26 Apr 2010

2. APD Simulation • 3rd generation geometry introduced • Input from Q. Ingram & I. Musienko • Epoxy layer about twice as thick as in 2G APD geometry (which was 200 m) • Further APD measurements could alter details • APD Digitization • Tag set in 3_7_0_pre1 that allows it • Choose APD geometry w/1 or 2 layers • APD digitization either added to crystal digis &/or separately (as an “MC truth”), controllable via cfg.py parameter • APD layer-gains controllable via cfg.py • What test(s) & validation(s) are required to use as default? The Real Thing • DPG has not yet addressed this to my knowledge B. Heltsley Simulation Mtg - 26 Apr 2010

3. APD Layout 3G (vertical not to scale) Capsule Crystal Ceramic Bulk Si Lo-gain active Si 1.65 mm Hi-gain active Si Non-depeleted Si 400 m 45 m 5 m 5mm Epoxy 0.1 m 375?m Silicone Glue 30 m Crystal B. Heltsley Simulation Mtg - 26 Apr 2010

4. Recent Noise Progress • Structural code changes allowing separate EB, EE correlation matrices completed in CMSSW_3_6_0_pre3, but values still set to identity • Tag set prepared using • measured correlations • Fixed, measured ’s (i.e. same for all channels) • online ZS/SR thresholds • Above tag set fully validated with REDIGI of MIN_BIAS MC (next slides) (lots of work by many people!!) • After we were late in the above validation, & had several glimmers of hope for 360_pre?, it has appeared in CMSSW_3_7_0_pre1 & been validated (& perhaps back-propagated to 3_6_1 ?). B. Heltsley Simulation Mtg - 26 Apr 2010

5. Commissioning-PromptReco-v7 vs REDIGI_MinBias7TeV EE+ EB EE- Occupancy Modeling Improves B. Heltsley Simulation Mtg - 26 Apr 2010

6. Commissioning-PromptReco-v7 vs REDIGI_MinBias7TeV EE- EE+ Data EB Timing Resolution Modeling Improves 354p1 354p1 B. Heltsley Simulation Mtg - 26 Apr 2010

7. ES Developments • Changes & validations from CM Kuo • Up until now, several ES MC values have been set in the cfg file only • Pedestals • Gain (hi or lo) • MIPtoADC • MIPtokeV • ZS threshold • ZS algorithm not same as online • Tag set & DB payloads created which fix the above • Got entangled with EB/EE noise model changes, & associated ES Reco code/DB changes, & is installed in CMSSW_3_7_0_pre1 (& perhaps back-propagated to 3_6_1 ?) New MC Old MC Data B. Heltsley Simulation Mtg - 26 Apr 2010

8. Sim changes in progress • Test containment factor • Sets overall MC energy normalization for EB & EE separately by looking at simulated single 50 GeV photons • Not sure if GEANT has changed since this was updated • Change from fixed, uniform single-sample ADC noise to measured channel-by-channel values? • Can test with only a cfg change. Who/when ? • Correlation matrix for ES (which has 3 time samples) • Ming & I are examining this • Would be much more efficient than current CPU & memory-intensive so-called “fast” method which tries to account for some of the correlations (ironically, with slower code) B. Heltsley Simulation Mtg - 26 Apr 2010

9. Simulation Housekeeping • These already done for 3_7_0_pre1 • Just 10 numbers per correlation matrix instead of 100 • Reform EB & EE analog hit response handling • Current practice makes a new CaloHitResponse object for all DetId’s (one ‘new’ & one ‘delete’ per DetId per event !) • New practice: create object once per job, modify • In progress • Reform digitized hit response handline • Has same problem as analog version, too many new ‘s & delete’s • Add ES digi creation to EB/EE templatized version, if possible • Inefficient ES Digi object (collection of std::vector<int> ) • Should look more like EB & EE Digi objects (long optimized) • F. Ferri & P. Gras agree • Migration would have to be carefully orchestrated • Looking at these & further changes for, possibly, 38X B. Heltsley Simulation Mtg - 26 Apr 2010

10. Backup slides B. Heltsley Simulation Mtg - 26 Apr 2010

11. Which Calos can be aligned? • Ecal • EB: barrel • EE: endcap • ES: preshower • Hcal • HB: barrel • HO: outer • HE: endcap • HF: forward • Forward • ZDC: zero-degree calorimeter @ 140m • Castor • CaloTower : a reco object which might need alignment B. Heltsley Simulation Mtg - 26 Apr 2010

12. Application of Calo Alignments • If applyAlignment parameter is set, a given calo has alignments applied • This part is part of generic/templated code • Alignment from GlobalAlignmentRcd for that calo applied for all volumes • Calo cells are grouped together into the physical construction objects for alignments • EB: by supermodule level (36 alignments) • EE: by Dee (4 alignments) • ES: by Dee and layer • Others in sensible groupings B. Heltsley Simulation Mtg - 26 Apr 2010

13. Short term alignment goals Insert global tracker alignment into various calo alignment slots in DB Load dummy ‘zero’ alignments payloads into DB Turn on alignment flags for calos Have this as a standard asap so that when alignments do become known, it is only a matter of inserting new payloads HAS NOT HAPPENED YET! B. Heltsley Simulation Mtg - 26 Apr 2010

14. Measuring Alignments • Three parallel efforts in progress • Preshower: Ming Kuo has begun examining offsets between projected tracks & hit strips in ES • Electrons (Ecal only) [no new work in >1 year] • Select an “appropriate” sample of electrons • Compare extrapolated Track to matched Supercluster position • For each e have an expected & measured position • Then, probably proceed in a manner similar to other alignment algorithms • Cosmic rays (Ecal & Hcal) • Cornell student Gala Nicolas-Kaufman beginning to help • Not yet demonstrated that it is useful • Start with zero-field data from CRAFT2009 B. Heltsley Simulation Mtg - 26 Apr 2010

15. EB, EE noise in simulation • See last month’s talk for details of issues • EB, EE noise simulation in <=CMSSW_3_6_0: • Needed time-correlations accounted for among ten samples for each crystal • Needed separate correlations for EB, EE • Had wrong single sample noise value • Had different SR/ZS thresholds than used online • Improvements were identified & tested • W/correlations, measured single sample noise can be used in simulation to improve agreement w/data • Ditto for ZS threshold B. Heltsley Simulation Mtg - 26 Apr 2010

16. Measured Correlations • Numbers from Sasha Ledovskoy • EB & EE have different correlations • Noise frequency is higher in EE than EB • Both have high correlations in neighboring samples B. Heltsley Simulation Mtg - 26 Apr 2010

17. RecHit Energy Spectrum MC/data agreement improves using measured (fixed) ’s, online ZS/SR:(EB)=1.089, ZS/SR(EB)=78.75 MeV;(EE)=2.018, ZS/SR(EE)=225 MeV From last month From David Petyt B. Heltsley Simulation Mtg - 26 Apr 2010

18. The Physical APD • Issues include: • What are relevant interactions? • Thermal neutrons? K0L ? e- ? • Can GEANT simulate any of this? • Thin layers • Special physics lists? • S. Banerjee investigating The Real Thing B. Heltsley Simulation Mtg - 26 Apr 2010

19. Tentative 2nd Generation APD “Ceramic” case 1.6mm Bulk Silicon 400µ Plastic Capsule 4mm Less sensitive 45µ Si Sensitive 5µ Si  Non-depeleted Si 0.1µ APD Geometry Implementation by B. Heltsley Epoxy 200µ Crystal S. Banerjee: making SimHits J. Branson: running studies B. Heltsley Simulation Mtg - 26 Apr 2010 Picture from iguana 3_5_0_pre5 Thicknesses magnified for visualization purposes

20. But is a simple APD good enough? • Perhaps • Perhaps not (Jim Branson et al.) • If Ecal spikes are related to APDs, perhaps more detail would help us understand what is happening • Details of APD response and local materials can potentially make a difference • e.g. Protective epoxy coating has ‘lots of oxygen’ which has larger neutron cross section. • Won’t know unless we try it, so… B. Heltsley Simulation Mtg - 26 Apr 2010

21. APD Names & materials from CMSCommonData/data/materials.xml • Numbered from 01-17 • # different barrel crystal shapes • Even though identical, must have different names because they reside in differently-named mother volumes • EAPD_nn: sensitive volume (higher gain): Si • EATJ_nn: sensitive volume (lower gain): Si • (“After The Junction”) • EGLU_nn: Epoxy: C (54%), H (13%), O(33%) • EBSi_nn: Bulk Si • ECER_nn: Ceramic (?) package: Si(30%), O(48%), K(6%) • Using Borosilicate_Glass until actual composition is known • EAND_nn: Non-Depleted layer: Si • ECAP_nn: PEEK Capsule: C (54%), H (13%), O(33%) B. Heltsley Simulation Mtg - 26 Apr 2010

22. Other views Side View, magnified thicknesses  Crystal Front View, Correct thicknesses  Crystal B. Heltsley Simulation Mtg - 26 Apr 2010

23. 5x5 mm2 APDs initially present in simulation as shown APD thickness magnified greatly for visualization purposes – actual (potentially active) thickness in original simulation is 5m. Material is Si. Inactive by default, but Sunanda Banerjee has a private tarball of changes to make these volumes active and generate SimHits. B. Heltsley Simulation Mtg - 26 Apr 2010

24. APD Layout (not to scale) Capsule Ceramic Bulk Si Lo-gain active Si 1.65 mm Hi-gain active Si Non-depeleted Si 400 m 45 m 5 m Epoxy 0.1 m 600m Silicone Glue 30 m Crystal B. Heltsley Simulation Mtg - 26 Apr 2010