1. Geant4 physics validation: Bragg Peak
P. Cirrone, G. Cuttone, F. Di Rosa, S. Guatelli, B. Mascialino, M. G. Pia, G. Russo
4th Workshop on Geant4 Bio-medical Developments,
Geant4 Physics Validation INF Genova, July 2005
Susanna Guatelli

2. Outline Brief summary of the Geant4 hadrontherapy application
Bragg peak test:
Validation of Geant4 electromagnetic and hadronic physics models
Susanna Guatelli

3. Scope of the hadrontherapy Geant4 application
Model accurately the CATANA hadrontherapy beam line
Calculate the energy deposit in a water phantom
Calculate the Bragg peak
Scattering system
Modulator & Range shifter
Monitor chambers
Ligth field
Laser
Susanna Guatelli

4. Bragg peak test
The CATANA group performs experimental measurements of the proton Bragg peak (see Giorgio’s talk)
Scope of the project: ~63 MeV proton Bragg peak validation
The Geant4 simulation models accurately the set-up of the experimental measurements
Comparison between the experimental measurements and the results of the simulation activating alternative electromagnetic and hadronic physics models
Susanna Guatelli

5. Particles: p, d, t, α, ions, e-, e+, pions, neutrons, muons
Physics component
The user can choose:
to activate EM physics only
to add on top the hadronic physics
to activate alternative models for both EM and hadronic physics
Modularised physics component
Particles: p, d, t, α, ions, e-, e+, pions, neutrons, muons
Susanna Guatelli

6. EM Physics models
The user can choose to activate for protons the following alternative models:
Low Energy - ICRU 49,
Low Energy - Ziegler77,
Low Energy - Ziegler85,
Low Energy Ziegler 2000,
Standard
The user can choose for d, t, α, ions the alternative models:
Low Energy ICRU,
In the case of Low Energy Physics, also the nuclear stopping power is activate
Susanna Guatelli

7. EM Physics models The user can choose to activate for e-:
LowEnergy EEDL,
LowEnergy Penelope,
Standard
The user can choose to activate for e+:
The user can choose to activate for gamma:
LowEnergy EPDL,
Susanna Guatelli

8. Hadronic physics Elastic scattering Inelastic scattering
Alternative approaches for p, n, pions
LEP ( E < 100 MeV) and Binary Ion model ( E > 80 MeV) for d, t, α
Neutron fission and capture
Susanna Guatelli

9. Hadronic physics list
The user can select alternative hadronic physics lists for protons, pions and neutrons
Precompound model
Binary model + Precompound model ( with all the option showed above)
Bertini model
LEP
+ default evaporation
+ GEM evaporation
+ default evaporation + Fermi Break-up
+ GEM evaporation + Fermi Break-up
Susanna Guatelli

10. Strategy Activate the electromagnetic physics only
Add on top the hadronic physics component
Simulate the Bragg peak with combinations of e.m. and hadronic physics models
Alternative hadronic physics models:
Precompound model only
+ default evaporation
+ GEM evaporation
+ default evaporation + Fermi Break-up
+ GEM evaporation + Fermi Break-up
Binary + Precompound model
Bertini model
LEP model
Alternative e.m. physics models:
Standard physics
Low Energy physics:
- ICRU49,
- Ziegler77,
- Ziegler85,
- SRIM2000
Susanna Guatelli

11. Bragg peak test
Compare experimental Bragg peak with simulation results
Quantitative analysis of the results
With the Statistical toolkit
Kolmogorov-Smirnov test to compare simulated and experimental set-up
Susanna Guatelli

12. First results
Susanna Guatelli

13. Projects for the future
Physics validation of the Bragg peak at higher proton beam energies
Physics validation of ion Bragg peak
Open to collaboration
Plan to publish a paper
Susanna Guatelli