Status of the Geant4 Physics Evaluation in ATLAS
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Transcript of Status of the Geant4 Physics Evaluation in ATLAS
Slide 1Slide 1
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
Peter LochUniversity of Arizona
Peter LochUniversity of Arizona
Status of the Geant4 Physics Evaluation in Status of the Geant4 Physics Evaluation in ATLASATLAS
Status of the Geant4 Physics Evaluation in Status of the Geant4 Physics Evaluation in ATLASATLAS
With contributions from D. Barberis1, K. Kordas2, A. Kiryunin2, R. Mazini2, B. Osculati1, G. Parrour2, A. Rimoldi3, P. Strizenec2, V. Tsulaia4, M.J. Varanda4 et al.
1 – ATLAS Inner Detector/Pixels2 – ATLAS Liquid Argon Calorimeters3 – ATLAS Muon System4 – ATLAS Tile Calorimeter
Slide 2Slide 2
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
Solenoid Forward Calorimeters (e)
Muon Detectors (μ)Electromagnetic Calorimeters (μ,e)
EndCap Toroid
Barrel Toroid Inner Detector (e,μ,π)Hadronic Calorimeters (e,μ,π) Shielding
EMB (LAr/Pb,Barrel)& EMEC (LAr/Pb,EndCap)
FCal (LAr/Cu/W)
HEC (LAr/Cu,EndCap) & TileCal (Scint/Fe,Barrel/Extended)
ATLAS: ATLAS: A Multi-Pur-A Multi-Pur-pose LHC pose LHC DetectorDetector
ATLAS: ATLAS: A Multi-Pur-A Multi-Pur-pose LHC pose LHC DetectorDetector
Slide 3Slide 3
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
Strategies for G4 physics validation in ATLASStrategies for G4 physics validation in ATLAS
Muon energy loss and secondaries production in Muon energy loss and secondaries production in the ATLAS calorimeters and muon detectorsthe ATLAS calorimeters and muon detectors
Electromagnetic shower simulations in calorimetersElectromagnetic shower simulations in calorimeters
Hadronic interactions in tracking devices and Hadronic interactions in tracking devices and calorimeterscalorimeters
ConclusionsConclusions
Strategies for G4 physics validation in ATLASStrategies for G4 physics validation in ATLAS
Muon energy loss and secondaries production in Muon energy loss and secondaries production in the ATLAS calorimeters and muon detectorsthe ATLAS calorimeters and muon detectors
Electromagnetic shower simulations in calorimetersElectromagnetic shower simulations in calorimeters
Hadronic interactions in tracking devices and Hadronic interactions in tracking devices and calorimeterscalorimeters
ConclusionsConclusions
This Talk:This Talk:
Slide 4Slide 4
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
Strategies for G4 Physics Validation in ATLAS
Strategies for G4 Physics Validation in ATLAS
Geant4 physics benchmarking: Geant4 physics benchmarking: compare features of interaction models with similar features in the old
Geant3.21 baseline (includes variables not accessible in the experiment); try to understand differences in applied models, like the effect of cuts
on simulation parameters in the different variable space (range cut vs energy threshold…);
Validation: Validation: use available experimental reference data from testbeams for various
sub-detectors and particle types to determine prediction power of models in Geant4 (and Geant3);
use different sensitivities of sub-detectors (energy loss, track multiplici-ties, shower shapes…) to estimate Geant4 performance;
tune Geant4 models (“physics lists”) and parameters (range cut) for optimal representation of the experimental detector signal with ALL relevant aspects;
Geant4 physics benchmarking: Geant4 physics benchmarking: compare features of interaction models with similar features in the old
Geant3.21 baseline (includes variables not accessible in the experiment); try to understand differences in applied models, like the effect of cuts
on simulation parameters in the different variable space (range cut vs energy threshold…);
Validation: Validation: use available experimental reference data from testbeams for various
sub-detectors and particle types to determine prediction power of models in Geant4 (and Geant3);
use different sensitivities of sub-detectors (energy loss, track multiplici-ties, shower shapes…) to estimate Geant4 performance;
tune Geant4 models (“physics lists”) and parameters (range cut) for optimal representation of the experimental detector signal with ALL relevant aspects;
Slide 5Slide 5
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
G4 Validation Strategies: Some Requirements…
G4 Validation Strategies: Some Requirements… Geometry description: Geometry description:
has to be as close as possible to the testbeam setup (active detectors
and relevant parts of the environment, like inactive materials in beams); identical in Geant3 and Geant4;
often common (simple) database used (muon detectors, calorimeters) to describe (testbeam) detectors in Geant3 and Geant4:
Environment in the experiment: Environment in the experiment: particles in simulations are generated following beam profiles (muon
detectors, calorimeters) and momentum spectra in testbeam (muon system);
features of electronic readout which can not be unfolded from experimental signal are modeled to best knowledge in simulation (incoherent and coherent electronic noise, digitization effect on signal…);
Geometry description: Geometry description: has to be as close as possible to the testbeam setup (active detectors
and relevant parts of the environment, like inactive materials in beams); identical in Geant3 and Geant4;
often common (simple) database used (muon detectors, calorimeters) to describe (testbeam) detectors in Geant3 and Geant4:
Environment in the experiment: Environment in the experiment: particles in simulations are generated following beam profiles (muon
detectors, calorimeters) and momentum spectra in testbeam (muon system);
features of electronic readout which can not be unfolded from experimental signal are modeled to best knowledge in simulation (incoherent and coherent electronic noise, digitization effect on signal…);
example: forward calorimeter uses actual machining and cabling database in simulations to describe electrode dimensions, locations and readout channel mapping;
example: forward calorimeter uses actual machining and cabling database in simulations to describe electrode dimensions, locations and readout channel mapping;
Slide 6Slide 6
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
Geant4 Setups (1)Geant4 Setups (1) Muon Detector Testbeam Muon Detector Testbeam
Detector plasticCover (3mm thick) Silicon sensor (280 μm thick)
FE chip (150 μm thick)PCB (1 mm thick)
Hadronic Interaction in Silicon Pixel Detector Hadronic Interaction in Silicon Pixel Detector
Slide 7Slide 7
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
Geant4 Setups (2)Geant4 Setups (2) Electromagnetic Barrel Accordion Calorimeter
Electromagnetic Barrel Accordion Calorimeter
10 GeV Electron Shower 10 GeV Electron Shower
Forward Calorimeter (FCal) Testbeam Setup
Forward Calorimeter (FCal) Testbeam Setup
FCal1 Module 0FCal1 Module 0
FCal2 Module 0FCal2 Module 0
ExcluderExcluder
Slide 8Slide 8
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
Muon Energy LossMuon Energy Loss
Reconstructed Energy [GeV]
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Electromagnetic Barrel Calorimeter EMB (Liquid Argon/Lead Accordion)
Electromagnetic Barrel Calorimeter EMB (Liquid Argon/Lead Accordion)
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Hadronic EndCap Calorimeter (HEC) (Liquid Argon/Copper Parallel Plate)
Hadronic EndCap Calorimeter (HEC) (Liquid Argon/Copper Parallel Plate)
G4 simulations (+ electronic noise) describe testbeam signals well, also in Tile Calorimeter (iron/scintillator technology, TileCal);
some range cut dependence of G4 signal due to contribution from electromagnetic halo (δ-electrons);
G4 simulations (+ electronic noise) describe testbeam signals well, also in Tile Calorimeter (iron/scintillator technology, TileCal);
some range cut dependence of G4 signal due to contribution from electromagnetic halo (δ-electrons);
Slide 9Slide 9
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
Secondaries Production by MuonsSecondaries Production by Muons
Muon Detector: Muon Detector: Muon Detector: Muon Detector:
extra hits produced in dedicated testbeam setup with Al and Fe targets (10, 20 and 30 cm deep), about ~37 cm from first chamber;
probability for extra hits measured in data at various muon energies (20-300 GeV);
Geant4 can reproduce the distance of the extra hit to the muon track quite well;
extra hit probability can be reproduced between 3 – 10% for Fe, some larger discrepancies (35%) remain for Al (preliminary analysis);
subject is still under study (more news expected in mid-October);
extra hits produced in dedicated testbeam setup with Al and Fe targets (10, 20 and 30 cm deep), about ~37 cm from first chamber;
probability for extra hits measured in data at various muon energies (20-300 GeV);
Geant4 can reproduce the distance of the extra hit to the muon track quite well;
extra hit probability can be reproduced between 3 – 10% for Fe, some larger discrepancies (35%) remain for Al (preliminary analysis);
subject is still under study (more news expected in mid-October);
Slide 10Slide 10
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
Geant4 Electron Response in ATLAS Calorimetry
Geant4 Electron Response in ATLAS Calorimetry
Overall signal characteristics:Overall signal characteristics:
Geant4 reproduces the average electron signal as func- tion of the incident energy in all ATLAS calorimeters very well (testbeam setup or analysis induced non-line- arities typically within ±1%)…
…but average signal can be smaller than in G3 and data (1-3% for 20- 700 μm range cut in HEC);
signal fluctuations in EMB very well simulated;
electromagnetic FCal: high energy limit of reso- lution function ~5% in G4, ~ 4% in data and G3;
Overall signal characteristics:Overall signal characteristics:
Geant4 reproduces the average electron signal as func- tion of the incident energy in all ATLAS calorimeters very well (testbeam setup or analysis induced non-line- arities typically within ±1%)…
…but average signal can be smaller than in G3 and data (1-3% for 20- 700 μm range cut in HEC);
signal fluctuations in EMB very well simulated;
electromagnetic FCal: high energy limit of reso- lution function ~5% in G4, ~ 4% in data and G3;
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GEANT4
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stochastic term
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data data
GEANT3GEANT3
GEANT4GEANT4
high energy limit %
TileCal: stochastic term 22%GeV1/2 G4/G3, 26%GeV1/2 data; high energy limit very comparable;
TileCal: stochastic term 22%GeV1/2 G4/G3, 26%GeV1/2 data; high energy limit very comparable;
FCal Electron ResponseFCal Electron Response
EMB Electron Energy Resolution
EMB Electron Energy Resolution
Slide 11Slide 11
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
Geant4 Electron Signal Range Cut Dependence
Geant4 Electron Signal Range Cut Dependence maximum signal in HEC and FCal found at 20 μm – unexpected signal drop
for lower range cuts;
HEC and FCal have very different readout geometries (parallel plate, tubular gap) and sampling characteristics, but identical absorber (Cu) and active (LAr) materials;
effect under discussion with Geant4 team (M. Maire et al.), but no solution yet (??);
maximum signal in HEC and FCal found at 20 μm – unexpected signal drop for lower range cuts;
HEC and FCal have very different readout geometries (parallel plate, tubular gap) and sampling characteristics, but identical absorber (Cu) and active (LAr) materials;
effect under discussion with Geant4 team (M. Maire et al.), but no solution yet (??);
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FCal 60 GeV ElectronsFCal 60 GeV Electrons HEC 100 GeV ElectronsHEC 100 GeV Electrons
20 μm 20 μm
Geant3 Geant3
Slide 12Slide 12
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
Electron Shower Shapes & Composition (1)
Electron Shower Shapes & Composition (1)
Shower shape analysis:Shower shape analysis:
Geant4 electromagnetic showers in the EMB are more compact longitudinally than in G3: about 3-13% less signal in the first 4.3X0, but 1.5-2.5% more signal in the following 16X0, and 5-15% less signal (large fluctuations) in the final 2X0 for 20-245 GeV electrons;
Geant4 electron shower in TileCal starts earlier and is slightly narrower than in G3:
Shower shape analysis:Shower shape analysis:
Geant4 electromagnetic showers in the EMB are more compact longitudinally than in G3: about 3-13% less signal in the first 4.3X0, but 1.5-2.5% more signal in the following 16X0, and 5-15% less signal (large fluctuations) in the final 2X0 for 20-245 GeV electrons;
Geant4 electron shower in TileCal starts earlier and is slightly narrower than in G3:
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Slide 13Slide 13
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
Electron Shower Shapes & Composition (2)
Electron Shower Shapes & Composition (2)
Shower composition:Shower composition:
cell signal significance spectrum is the distribution of the signal-to-noise ratio in all individual channels for all electrons of a given impact energy;
to measure this spectrum for simu- lations requires modeling of noise in each channel in all simulated events (here: overlay experimental “empty” noise events on top of Geant4 events)
spectrum shows higher end point for data than for Geant4 and Geant3, indicating that larger (more significant) cell signals occur more often in the experiment -> denser showers on average;
Shower composition:Shower composition:
cell signal significance spectrum is the distribution of the signal-to-noise ratio in all individual channels for all electrons of a given impact energy;
to measure this spectrum for simu- lations requires modeling of noise in each channel in all simulated events (here: overlay experimental “empty” noise events on top of Geant4 events)
spectrum shows higher end point for data than for Geant4 and Geant3, indicating that larger (more significant) cell signals occur more often in the experiment -> denser showers on average;
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FCal 60 GeV Electrons
excess in experimentexcess in
experiment
Slide 14Slide 14
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
Individual Hadronic InteractionsIndividual Hadronic Interactions
Inelastic interaction properties:Inelastic interaction properties:
energy from nuclear break-up in the course of a hadronic inelastic interactions causes large signals in the silicon pixel detector in ATLAS, if a pixel (small, 50 μm x 400 μm), is directly hit;
this gives access to tests of single hadronic interaction modeling, especially concerning the nuclear part;
testbeam setup of pixel detectors supports the study of these interactions;
presently two models in Geant4 studied: the parametric “GHEISHA”-type model (PM) and the quark-gluon string model (QGS, H.P. Wellisch);
Inelastic interaction properties:Inelastic interaction properties:
energy from nuclear break-up in the course of a hadronic inelastic interactions causes large signals in the silicon pixel detector in ATLAS, if a pixel (small, 50 μm x 400 μm), is directly hit;
this gives access to tests of single hadronic interaction modeling, especially concerning the nuclear part;
testbeam setup of pixel detectors supports the study of these interactions;
presently two models in Geant4 studied: the parametric “GHEISHA”-type model (PM) and the quark-gluon string model (QGS, H.P. Wellisch);
Special interaction trigger
~3000 sensitive pixels
Slide 15Slide 15
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
Individual Hadronic Interactions: Energy Release
Individual Hadronic Interactions: Energy Release
Interaction cluster:Interaction cluster:
differences in shape and average (~5% too small for PM, ~7% too small for QGS) of released energy distribution for 180 GeV pions in interaction clusters;
fraction of maximum single pixel release and total cluster energy release not very well reproduced by PM (shape, average ~26% too small);
QGS does better job on average (identical to data) for this variable, but still shape not completely reproduced yet (energy sharing between pixels in cluster);
Interaction cluster:Interaction cluster:
differences in shape and average (~5% too small for PM, ~7% too small for QGS) of released energy distribution for 180 GeV pions in interaction clusters;
fraction of maximum single pixel release and total cluster energy release not very well reproduced by PM (shape, average ~26% too small);
QGS does better job on average (identical to data) for this variable, but still shape not completely reproduced yet (energy sharing between pixels in cluster);
PM QGS Experiment
PM QGS Experiment
log(energy equivalent # of electrons)
Slide 16Slide 16
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
More on Individual Hadronic InteractionsMore on Individual Hadronic Interactions
Spread of energy:Spread of energy:
other variables tested with pixel detector: cluster width, longest distance between hit pixel and cluster barycenter -> no clear preference for one of the chosen models at this time (most problems with shapes of distributions);
Charged track multiplicity:Charged track multiplicity:
average charged track multiplicity in in-elastic hadronic interaction described wellwith both models (within 2-3%), with aslight preference for PM;
Spread of energy:Spread of energy:
other variables tested with pixel detector: cluster width, longest distance between hit pixel and cluster barycenter -> no clear preference for one of the chosen models at this time (most problems with shapes of distributions);
Charged track multiplicity:Charged track multiplicity:
average charged track multiplicity in in-elastic hadronic interaction described wellwith both models (within 2-3%), with aslight preference for PM;
PM QGS Experiment
Slide 17Slide 17
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
Geant4 Hadronic Signals in ATLAS Calorimeters
Geant4 Hadronic Signals in ATLAS Calorimeters
Calorimeter pion response:Calorimeter pion response:
after discovery of “mix-and-match” problem (transition from low energy to high energy char-ged pion models) in the deposited energy from energy loss of charged particles in pion showers in the HEC (G4 4.0, early 2002): fixes suggested by H.P. Wellisch (LHEP, new energy thresholds in model transition + code changes) and QGS model tested;
e/π signal ration in HEC and TileCal still not well reproduced by Geant4 QGS or LHEP - but better than with GCalor in Geant3.21;
energy dependence in HEC in QGS smoother, “discontinuities” between ~20 GeV and ~80 GeV gone;
Calorimeter pion response:Calorimeter pion response:
after discovery of “mix-and-match” problem (transition from low energy to high energy char-ged pion models) in the deposited energy from energy loss of charged particles in pion showers in the HEC (G4 4.0, early 2002): fixes suggested by H.P. Wellisch (LHEP, new energy thresholds in model transition + code changes) and QGS model tested;
e/π signal ration in HEC and TileCal still not well reproduced by Geant4 QGS or LHEP - but better than with GCalor in Geant3.21;
energy dependence in HEC in QGS smoother, “discontinuities” between ~20 GeV and ~80 GeV gone;
HEC Pions
QGS
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Slide 18Slide 18
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
Geant4 Hadronic Signal Characteristics (1)Geant4 Hadronic Signal Characteristics (1)
Pion energy resolution:Pion energy resolution:
good description of experimental pion energy resolution by QGS in TileCal; LHEP cannot describe stochastic term, but fits correct high energy limit;
larger discrepancies in HEC: stochastic term significantly too large for QGS and LHEP, but reasonable description of high energy behaviour by QGS;
Pion energy resolution:Pion energy resolution:
good description of experimental pion energy resolution by QGS in TileCal; LHEP cannot describe stochastic term, but fits correct high energy limit;
larger discrepancies in HEC: stochastic term significantly too large for QGS and LHEP, but reasonable description of high energy behaviour by QGS;
QGS
G
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σ = 64.44±1.03 % GeV 4.70±0.16 %E
σ = 68.89±1.46 % GeV 5.82±0.14 %E
.17 %E
HEC Pion Energy Resolution
TileCal Pion Energy Resolution
Pion energy [GeV]
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Slide 19Slide 19
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
Pion longitudinal shower profiles:Pion longitudinal shower profiles:
measured by energy sharing in four depth segments of HEC; both Geant4 models (LHEP and QGS) studied;
rather poor description of experimental energy sharing by QGS; pion showers start too early;
LHEP describes longitudinal energy sharing in the experiment quite well for pions in the the studied energy range 20-200 GeV (at the same level as GCalor in Geant3.21);
Pion longitudinal shower profiles:Pion longitudinal shower profiles:
measured by energy sharing in four depth segments of HEC; both Geant4 models (LHEP and QGS) studied;
rather poor description of experimental energy sharing by QGS; pion showers start too early;
LHEP describes longitudinal energy sharing in the experiment quite well for pions in the the studied energy range 20-200 GeV (at the same level as GCalor in Geant3.21);
Geant4 Hadronic Signal Characteristics (2)Geant4 Hadronic Signal Characteristics (2)
Slide 20Slide 20
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
Conclusions (1):Conclusions (1):
Geant4 can simulate relevant features of muon, electron and Geant4 can simulate relevant features of muon, electron and pion signals in various ATLAS detectors, often better than pion signals in various ATLAS detectors, often better than Geant3;Geant3;
remaining discrepancies, especially for hadrons, are remaining discrepancies, especially for hadrons, are addressed and progress can be expected in the near future;addressed and progress can be expected in the near future;
ATLAS has a huge amount of appropriate testbeam data for ATLAS has a huge amount of appropriate testbeam data for the calorimeters, inner detector modules, and the muon the calorimeters, inner detector modules, and the muon detectors to evaluate the Geant4 physics models in detail;detectors to evaluate the Geant4 physics models in detail;
feedback loops to Geant4 team are for most systems feedback loops to Geant4 team are for most systems established since quite some time; communication is not a established since quite some time; communication is not a problem;problem;
Geant4 can simulate relevant features of muon, electron and Geant4 can simulate relevant features of muon, electron and pion signals in various ATLAS detectors, often better than pion signals in various ATLAS detectors, often better than Geant3;Geant3;
remaining discrepancies, especially for hadrons, are remaining discrepancies, especially for hadrons, are addressed and progress can be expected in the near future;addressed and progress can be expected in the near future;
ATLAS has a huge amount of appropriate testbeam data for ATLAS has a huge amount of appropriate testbeam data for the calorimeters, inner detector modules, and the muon the calorimeters, inner detector modules, and the muon detectors to evaluate the Geant4 physics models in detail;detectors to evaluate the Geant4 physics models in detail;
feedback loops to Geant4 team are for most systems feedback loops to Geant4 team are for most systems established since quite some time; communication is not a established since quite some time; communication is not a problem;problem;
Slide 21Slide 21
Peter LochUniversity of Arizona
Tucson, Arizona 85721
Status of the GEANT4 Physics Evaluation in ATLASGeant4 WorkshopGeant4 Workshop
September 30, September 30, 20022002
lack of man power in all ATLAS systems makes it hard to lack of man power in all ATLAS systems makes it hard to follow up on Geant4 progress; hard to catch up with G4 follow up on Geant4 progress; hard to catch up with G4 evolution! Need to look into more automated benchmark tests ??evolution! Need to look into more automated benchmark tests ??
Geant4 is definitively a mature and useful product for large Geant4 is definitively a mature and useful product for large scale detector response simulations!scale detector response simulations!
lack of man power in all ATLAS systems makes it hard to lack of man power in all ATLAS systems makes it hard to follow up on Geant4 progress; hard to catch up with G4 follow up on Geant4 progress; hard to catch up with G4 evolution! Need to look into more automated benchmark tests ??evolution! Need to look into more automated benchmark tests ??
Geant4 is definitively a mature and useful product for large Geant4 is definitively a mature and useful product for large scale detector response simulations!scale detector response simulations!
Conclusions (2):Conclusions (2):