Speaker
Description
Despite their frequent use, the hadronic models implemented in Geant4 have shown severe limitations in
reproducing the measured yield of secondaries in ions interaction below 100 MeV/A, in term of
production rates, angular and energy distributions [1,2,3]. We will present a benchmark of the Geant4
models with double-differential cross section and angular distributions of the secondary fragments
produced in the 12C fragmentation at 62 MeV/A on thin carbon target; such a benchmark includes the
recently implemented model INCL++ [4,5]. Moreover, we will present the preliminary results, obtained
in simulating the same interaction, with SMF [6] and BLOB [7]. Both, SMF and BLOB are semiclassical
one-body approaches to solve the Boltzmann-Langevin equation. They include an identical treatment of
the mean-field propagation, on the basis of the same effective interaction, but they differ in the way
fluctuations are included.
In particular, while SMF employs a Uehling-Uhlenbeck collision term and introduces fluctuations as
projected on the density space, BLOB introduces fluctuations in full phase space through a modified
collision term where nucleon-nucleon correlations are explicitly involved. Both of them, SMF and BLOB,
have been developed to simulate the heavy ion interactions in the Fermi-energy regime. We will show
their capabilities in describing 12C fragmentation coupled with the de-excitation phase of Geant4, as their
implementation in Geant4 is foreseen.
[1] B. Braunn et al. “Comparisons of hadrontherapy-relevant data to nuclear interaction codes in the
Geant4 toolkit,” J. Phys.: Conf. Ser., 2013, vol. 420, p. 012163
[2] M. De Napoli et al. “Carbon fragmentation measurements and validation of the Geant4 nuclear
reaction models for hadrontherapy,” Phys. Med. Biol., 2012, vol. 57, no. 22, pp. 7651–7671.
[3] J. Dudouet et al. “Benchmarking geant4 nuclear models for hadron therapy with 95
MeV/nucleon carbon ions,” Phys. Rev. C, 2014, vol. 89, no. 5, p. 054616.
[4] A. Boudard et al. “New potentialities of the Liège intranuclear cascade model for reactions
induced by nucleons and light charged particles” Phys. Rev. C, 2013, vol. 87, p. 014606.
[5] D. Mancusi et al., “Extension of the Liège intranuclear-cascade model to reactions induced by
light nuclei” Phys. Rev. C, 2014, vol. 90 p. 054602.
[6] M. Colonna et al. “Fluctuations and dynamical instabilities in heavy-ion reactions,” Nucl. Phys.,
1998, vol. A642, p. 449
[7] P. Napolitani and M. Colonna “Bifurcations in Boltzmann-Langevin one body dynamics for
fermionic systems”, 2013, Phys. Lett. B vol. 726, pp. 382-386
