1. A. Chukanov, S. Dmitrievsky, Yu. Gornushkin, D. Naumov JINR, Dubna Opera collaboration meeting 9 th March 2011, Nagoya

2.  Signal attenuation in strips  Cross-talks simulation  Geant 4 running  Summary

3. Signals from an isolated muon Signals from the left and right PMT’s are not well discribed by MC

4. Model of light attenuation in a fiber PMT left PMT right E left E right 0 x E0E0 L 0 = 686 cm dL

5. OpDigit: parametrization from muon tracks.16 different parameters for light attenuations for all detector Parametrization according to attenuation distributions for all detector (calibration)

6. Signals from an isolated muon OpDigit New para- metrization

7. Δ=9 Δ=-1 Δ=7 Δ=8 Δ=1 Δ=-7 Δ=-8 Δ=-9 1 8 56 64 PMT Measured CT fraction is equal 7.4%.

8. CT Energy/Energy in plane, Threshold = 0.3 p.e. Measured from muon tracks CT fraction: 5.3%

9. v 4.0 new

10. VMC allow us to use different tracing programs:  Geant 3  Geant 4  Fluka (for internal use only) Only Geant 3 is using now

11. “OPERA” particle replaces  and charm Charmed hadrons and  -leptons are decayed in PYTHIA New names were introduced Valid for the  -leptons Not valid for the charmed hadrons Geant 4 crashs because of introduction of “OPERA” particles   Charmed hadrons

12.  OpSim scripts modification (manual is coming soon)  Short live particles do not decay at event genertion level  PYTHIA as external decay program at particle transportation level Longer computation time, need to choose proper physics list

13. GEANT 3 GEANT 4

14.  TT fibers attenuation from testing beam gives a better Data by MC description  Recalculated cross-talks fraction from 7.4% to 5.3%  Migration to Geant 4 as transportation program