LAr Response to pions: Data vs MC

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

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 • mA2MEV 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) LAr response to pions

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

ADC -> MeV for MC and Data (10.0.2) Monte Carlo: LArdigitMaker.cxx Data: LArRawChannelSimpleBuilder.cxx Differences at present: • Difference in the Sampling Fractions • Different noise normalization due to ADC2MeV (small) LAr response to pions

Data: 3x3 LAr vs Total tile Energy Pion LAr MIPs Electrons LAr response to pions

Beam Profiles MC Data Can do better LAr response to pions

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 LAr response to pions

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? • ... LAr response to pions

MuTag: removes a portion of muons LAr response to pions

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

Noise: ADC[2] eta=10, phi=8 DATA MC LAr response to pions

Noise: ADCpeak DATA MC LAr response to pions

Noise: Reduce the MC noise to 0.6 DATA MC Great match! However … LAr response to pions

Noise: ADCpeak still wider! DATA MC LAr response to pions

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

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

Visible Energy per LAr Sampling Normalization away from the noise region Less energy in MC More energy in MC LAr response to pions

Total visible Energy (LAr) Normalization away from the noise region LAr response to pions

Summary • 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 LAr response to pions

Supporting Viewgraphs LAr response to pions

ADC2MEV (Data vs MC) LAr response to pions

How to get the SF for Data (an example) SF(Presampler h<0.8)=t*W/e/1250 = 0.0496 SF(Accordion h<0.8)=t*W/e/370.37 = 0.18718 LAr response to pions

LAr Response to pions: Data vs MC