ECAL and HCAL Simulation Status Rick Wilkinson Fabio Cossutti

Simulation Sim Hit: Sim Hit: One ns of energy deposit in an active volume Sunanda Banerjee) Done by GEANT4 (Sunanda Banerjee) Depends strongly on geometry modeling ECAL (Paolo Meridiani) ECAL (Paolo Meridiani) HCAL (Jeremy Mans) HCAL (Jeremy Mans)

Digitization Digitization includes: pulse shape, pileup, amplification, noise, ADC encoding, trig prims, zero suppression Digitization includes: pulse shape, pileup, amplification, noise, ADC encoding, trig prims, zero suppression CMSSW Digitization has details not in ORCA CMSSW Digitization has details not in ORCA Common framework for all systems (Wilkinson) Common framework for all systems (Wilkinson) ECAL (Cossutti, P. Govoni, Wilkinson) ECAL (Cossutti, P. Govoni, Wilkinson) HCAL (Fedor Ratnikov, Wilkinson) HCAL (Fedor Ratnikov, Wilkinson) Preshower (Chia-Ming Kuo) Preshower (Chia-Ming Kuo)

Digitization using Calibration? Allows added realism Allows added realism Make hot channels hot, noisy channels noisy Make hot channels hot, noisy channels noisy Allows blind test of calibration techniques Allows blind test of calibration techniques Simulate the data with one set of constants Simulate the data with one set of constants Use derived calibration for reconstruction Use derived calibration for reconstruction

Noises Pedestal Pedestal width Gain Width ECAL Barrel 200 ADC 1.26 ADC (40 MeV) 0.3 % Rear non-uniformity Front done in OSCAR ECAL Endcap 200 ADC 2.87 ADC (150 MeV) 0.3 % HCAL 5 ADC (0.75 GeV) 0.56 ADC (0.1 GeV) 0 HF 2 ADC (0.75 GeV) 0.3 ADC (0.14 GeV) 0

Photostatistics Photoelectrons / GeV 1 / sqrt(N) ECAL Barrel % / sqrt(E) ECAL Endcap % / sqrt(E) Photoelectrons / GeV Sampling Frac. HCAL (HB) HCAL (HE) HCAL (HO) HCAL (HF1) HCAL (HF2) 2.091

ECAL Digitization: Details (Fabio Cossutti) Gain Switching (including hysteresis) Gain Switching (including hysteresis) Calibration Interface (Shahram Rahatlou) Calibration Interface (Shahram Rahatlou) No database access yet, just interface No database access yet, just interface Uses gain ratios, pedestals, & widths Uses gain ratios, pedestals, & widths Correlated Noise Correlated Noise Implemented with a global correlation matrix Implemented with a global correlation matrix Currently a unit matrix Currently a unit matrix

HCAL Digitization: Details Layer 0: Weighting done by GEANT4 (Banerjee) Layer 0: Weighting done by GEANT4 (Banerjee) Calibration Interface (Fedor Ratnikov) Calibration Interface (Fedor Ratnikov) Fetch pedestals, gains, & noise Fetch pedestals, gains, & noise For each of four capacitors in channel For each of four capacitors in channel Time Slew (Jeremy Mans) Time Slew (Jeremy Mans) Small signals delayed by ~10 ns Small signals delayed by ~10 ns Correlated Noise Correlated Noise Effect is big in HCAL (Michal Szleper) Effect is big in HCAL (Michal Szleper) Not simulated, but infrastructure exists Not simulated, but infrastructure exists

Trig Prims ECAL Trig Prims (Ursula Berthon) ECAL Trig Prims (Ursula Berthon) HCAL Trig Prims (Jeremy Mans) HCAL Trig Prims (Jeremy Mans)

Zero Suppression ECAL Selective Readout (Philippe Gras) ECAL Selective Readout (Philippe Gras) Trig prim > 5 GeV: read all 25x25 crystals Trig prim > 5 GeV: read all 25x25 crystals Trig prim > 2.5 GeV: read 5x5 crystals Trig prim > 2.5 GeV: read 5x5 crystals Otherwise Otherwise 90 MeV threshold in barrel 90 MeV threshold in barrel 450 MeV in endcap 450 MeV in endcap HCAL Zero Suppression (Jeremy Mans) HCAL Zero Suppression (Jeremy Mans) Pedestal-subtracted amplitudes Pedestal-subtracted amplitudes Can store both suppressed & unsuppressed digis Can store both suppressed & unsuppressed digis

Validation ECAL Hits (Xingtao Huang) Hits (Xingtao Huang) Digis (F. Cossutti) Digis (F. Cossutti) RecHits (Chiara Rovelli) RecHits (Chiara Rovelli) 30 GeV photons 400 GeV photons 60 GeV pions Neutrinos (for noise) HCAL Salavat AbdullinHits (Salavat Abdullin) Dmitri KonstantinovDigis (Dmitri Konstantinov) 100 GeV Pions

ECAL Simulation Plans New Geometry (Brian Heltsley) New Geometry (Brian Heltsley) Handles material behind the crystals better Handles material behind the crystals better Important for HCAL Important for HCAL Study shower shape Study shower shape ~1% discrepancy, maybe Cerenkov ~1% discrepancy, maybe Cerenkov Energy deposit inside APD Energy deposit inside APD