Francesco Longo University of Trieste and INFN-Trieste After some discussion at Perugia meeting (P.Boinee, R.Rando, R.Giannitrapani, J.Cohen-Tanugi) Analysis Group Validation of G4: status, prospects & discussions

2 Setup for the study (F.Longo and J.Cohen Tanugi) Standalone G4 tests use MC information to retrieve deflection angle between initial and final direction of an normally incident charged track. Converting Volume is a Tungstene Slab: thin (0.105 mm) and thick (0.723mm) Projected angle is computed as: arcsin(p_f.x()/p_f.mag()) Test is to compare its distribution to Moliere formula (pdg 26.10), 1 and 10 GeV mu and e-

3 MCS status and developments  Note that G4 uses another model than Moliere theory  Discrepancy for muons at the 20-24% level in G4.5.1  Contacts with G4 developers at CERN  Bug fix in G4.5.2 (ok for muons and protons)  For e-? G4 developers model fits well data on e- (low energy) could we give them more data?  Using the Moliere theory also for e-?

4 G4 physics validation

5 Koi (SLAC)

6 G4 physics validation

7 Preliminary (not released with G4 5.2)

8 G4 validation for DC1 Photon processes Photoelectric, Compton, Pair production Cross Section Angular Distribution Energy distribution Charged particle processes Ionisation Landau, Bethe Bloch Range, Stopping Power, Straggling Multiple Scattering Projected Angle, Energy dependence Bremsstrahlung Cross Section, Angular Distribution, Energy Distribution Delta ray production Energy distribution, Multiplicity Positron Annihilation Cross section EM shower profile Mizuno’s thesis confirmation

9 G4Validation Geant4 test and analysis G4 comparison projects: E.g. ATLASATLAS GLAST validation: GEANT4TEST package in systests Low level validation on “Gleam level” High level comparison (Baloon, EM, test beam(s), …) Requirements from Subsystems Statistical methods?