1. LAr Response to pions: Data vs MC S.Paganis (Wisconsin) with Isabelle Winterger,Martin Aleksa LAr Week CTB Meeting, CERN, 10-May-2005

2. 10-May-2005LAr response to pions2 Analysis (10.0.2 data+MC)  Run: 2100482 20GeV pions Fully combined, have shown previously problems in LAr rec. energy  Parabola Energy reconstruction 15ADC “cubicADCcut” in LArRawChannelSimpleBuilder.cxx  A2MEV numbers from EMTB  EMTB 3x3 clustering  No cluster corrections, No Long. weigths  No shower cuts yet.  MC: 20k events Charge collection corrections Tried to get “correct” beam profile … ADC2MEV in Digitization step (parabola is the default)

3. 10-May-2005LAr response to pions3 Program Flow ( release 10.0.2 ): Analysis C++ Package MC: ADC2MEV happens here Thanks to: Manuel Galas Final Physics Plots jobOptions.G4Ctb_Dig.py Reconstruction ESD and CBNT Data: ADC2MEV here CTB04 Data jobOptions.G4Ctb_Sim.py TBAnalysis on ESD miniCBNT +G4Apps

4. 10-May-2005LAr response to pions4 ADC -> MeV for MC and Data (10.0.2) Monte Carlo: LArdigitMaker.cxx Data: LArRawChannelSimpleBuilder.cxx Differences at present : 1.Difference in the Sampling Fractions 2.Different noise normalization due to ADC2MeV (small)

5. 10-May-2005LAr response to pions5 Data: 3x3 LAr vs Total tile Energy Electrons Pion LAr MIPs

6. 10-May-2005LAr response to pions6 Beam Profiles Can do better Data MC

7. 10-May-2005LAr response to pions7 Cleaning cuts  For reconstructed energy comparisons: E(MC) = Erec * SFmc/SFdata  For visible energy comparisons: E(MC) = Erec * SFmc E(data) = Erec * SFdata  muTag to remove muons  Etile+ELAr MIP cuts to remove muons  ELAr>15GeV, to remove electrons (crude) Don’t want to use shower shape cuts yet (under study) Possible Long electron tail

8. 10-May-2005LAr response to pions8 Possible biases:  Tile MC has no noise.  For data a LAr drift time assumption is made to get the SF  LAr MC has noise but it does not perfectly represent the data  Cuts on LAr energy cause a bias when scale and shape are different  Parabolic fit at low energies? ...

9. 10-May-2005LAr response to pions9 MuTag: removes a portion of muons

10. 10-May-2005LAr response to pions10 Zoom in the “MIP” region (after cuts) MC is broader, slow rising: due to more noise or the parabola or …? OLD Plot: April 2005: we care because MIP region is upstream material insensitive!

11. 10-May-2005LAr response to pions11 Noise: ADC[2] eta=10, phi=8 DATAMC

12. 10-May-2005LAr response to pions12 Noise: ADCpeak DATAMC

13. 10-May-2005LAr response to pions13 Noise: Reduce the MC noise to 0.6 DATAMC Great match! However …

14. 10-May-2005LAr response to pions14 Noise: ADCpeak still wider! DATAMC

15. 10-May-2005LAr response to pions15 Zoom in the “MIP” region (after cuts) Improved agreement and an indication of the MC EM scale being a few % too low. However, in the data 5ns ~ 1% New Plot: after reducing accordion noise in MC. we care because MIP region is upstream material insensitive!

16. 10-May-2005LAr response to pions16 LAr Energy after simple cuts Data MC Some disagreement between data and MC after only SF adjustment. It seems that there is additional upstream material, not present in the simulation.

17. 10-May-2005LAr response to pions17 Visible Energy per LAr Sampling More energy in MC Less energy in MC Normalization away from the noise region

18. 10-May-2005LAr response to pions18 Total visible Energy (LAr) Normalization away from the noise region

19. 10-May-2005LAr response to pions19Summary  Reasonable but not perfect agreement between Data and MC: MIP region indicates lower EM MC response (few %) Strips vs Middle response indicates some missing material in the MC description (must be checked).  Discrepancy between DATA and MC for very small depositions was resolved: due to inconsistent noise in MC and due to the ADCpeak parabola calculation (move to OFCs)  Tile colleagues confirmed MC improvement. Will try to communicate the present progress. Next round, use OFCs

20. 10-May-2005LAr response to pions20 Supporting Viewgraphs

21. 10-May-2005LAr response to pions21 ADC2MEV (Data vs MC) ADC2DACDAC2Volt Volts2  A  A2MeV How:Ramps 38.147 uA/Volt Injection Resistor (t drift *W)/e  1/SF PS (EMB1) 38.147/R=0.114 nA 1250 S1 (EMB1) 12.62 nA 370.3703 S2 (EMB1) 37.58 nA 370.3703 S3 (EMB1) 37.58 nA 370.3703

22. 10-May-2005LAr response to pions22 How to get the SF for Data (an example) SF(Presampler <0.8)=t*W/e/1250 = 0.0496 SF(Accordion <0.8)=t*W/e/370.37 = 0.18718