Extension of the Liège intranuclear cascade model at incident energies between 2 and 12 GeV. Aspects of pion production

Abstract

The validity of the standard version of the Liège Intra-Nuclear Cascade (INCL4) model, which has been shown to be quite successful for the description of spallation reactions, is limited to an upper incident energy of ∼2 GeV, because inelastic elementary processes are restricted to the excitation and de-excitation of the Delta resonance. In this paper, the INCL4 model is extended to higher incident energy by including other inelastic elementary collisions. However, excitation of heavier baryonic resonances is replaced by direct multipion production in elementary nucleon-nucleon and pion-nucleon collisions. The predictions of the modified model for production of charged pions by proton and pion beams off nuclei are compared with experimental data of the HARP Collaboration for beam energies between 2 and 12 GeV. The apparent duality between the approach based on excitation of numerous baryonic resonances and our approach is briefly discussed.

Extension of the Liège intranuclear-cascade model to reactions induced by light nuclei

“…Further details are available in Refs. [101,102]. Figure 35 above shows a map of models for the INCL++-based physics lists in GEANT4 v10.1β.…”

Recent Developments of the Liège Intranuclear Cascade Model in View of its Use into High-energy Transport Codes

“…Further improvements, in particular to make the model for projectile-target symmetrical, and more systematic tests are under progress. A version extended to higher energies has also been developed [22] in which multi-pion channels have been added. Inclusion of strange particle production is also foreseen.…”

On the search for a (n,f) cross-section reference at intermediate energies

“…[1] in the energy range from 100 MeV to 1 GeV, a self-consistent determination of the stopping time of the fast cascade [13] makes it possible to skip the pre-equilibrium stage, so as to reduce intermediate energy fission to a two stage process. In the Monte Carlo simulation code (Bologna's MC onwards) used in this work in an extended energy range up to 2 GeV, version 5.2 [14] of INCL++ was adopted, including multiple pion production [15] that allows, in principle, calculations up to 10-12 GeV, while version 5.1.14 adopted in Ref. [1] permitted only single pion production from the delta resonance decays; the versions of the evaporation fission models yielding fission cross sections, GEMINI++ and ABLA07, are those distributed with version 5.2 of INCL++, containing significant changes with respect to the versions adopted in Ref.…”