QGSM development for spallation reactions modeling

M.I Baznat,K.K Gudima,S.E Chigrinov,S Ershov,T Shneydman,A Zubov,A Vdovin

doi:10.1051/epjconf/20123817003

Abstract

The growing interest in spallation neutron sources, accelerator-driven systems, R&D of rare isotope beams, and development of external beam radiation therapy necessitated the improvement of nuclear reaction models for both stand-alone codes for the analysis of nuclear reactions and event generators within the Monte Carlo transport systems for calculations of interactions of high-energy particles with matter in a wide range of energy and in arbitrary 3D geometry of multicomponent targets. The exclusive approach to the description of nuclear reactions is the most effective for detailed calculation of inelastic interactions with atomic nuclei. It provides the correct description of particle production, single- and double-differential spectra, recoil, and fission product yields. This approach has been realized in the Quark Gluon String Model (QGSM) for nuclear reactions induced by photons, hadrons, and high energy heavy ions. In this article, improved versions of the QGSM model and a corresponding code have been developed tested and bench marked against experimental data for neutron production in spallation reactions on thin and thick targets in the energy range from a few MeV to several GeV/nucleon.

Highlights

The Quark Gluon String Model (QGSM) [1,2,3] model describes properly the interactions of particles and ions with matter at energies far beyond the reactor diapason, from tens of MeV to several GeV, where the experimental data are rather scarce so that the development of fast and reliable methods for simulation of transport of high-energy photons, pions neutrons, protons, and ions becomes the major challenge
The growing interest in spallation neutron sources, accelerator-driven systems, R&D of rare isotope beams, and development of external beam radiation therapy necessitated the improvement of nuclear reaction models for both stand-alone codes for the analysis of nuclear reactions and event generators within the Monte Carlo transport systems for calculations of interactions of high-energy particles with matter in a wide range of energy and in arbitrary 3D geometry of multicomponent targets
The exclusive approach to the description of nuclear reactions is the most effective for detailed calculation of inelastic interactions with atomic nuclei. It provides the correct description of particle production, single- and double-differential spectra, recoil, and fission product yields. This approach has been realized in the Quark Gluon String Model (QGSM) for nuclear reactions induced by photons, hadrons, and high energy heavy ions

Summary

Introduction

The QGSM [1,2,3] model describes properly the interactions of particles and ions with matter at energies far beyond the reactor diapason, from tens of MeV to several GeV, where the experimental data are rather scarce so that the development of fast and reliable methods for simulation of transport of high-energy photons, pions neutrons, protons, and ions becomes the major challenge. - new compilations and parametrization of elastic, inelastic, and total hN and πN cross sections in the above energy range; -more precise and effective model for calculation of inelastic NN, πN and γN interactions with formation of a shortlived ∆ and N∗ -resonances followed by its decay into a pion and a nucleon; - fast MC algorithms for calculation of these interactions; - formation of light nuclear fragments in the coalescence model, emission of photons on the de-excitation stage of reaction, and a more accurate description of the competition between the processes of particle evaporation, light nucleus evaporation and fission; - more precise approach to modeling high-energy hadronhadron interactions, γN and γd interactions; - implementation of new code as event generator into transport code SHIELD [4] for calculation of interactions of hadron and heavy ion beams with thick targets This allows us to perform the analysis of the most important aspect of spallation reaction — neutron production from interactions of proton, pion, antiproton, H2 and, He3 with thin and thick Ag, Au, Ta, Pb, Bi, U targets in the energy range from ∼0.5 GeV up to 5.0 GeV

Modification of evaporation and fission in QGSM code

The total radiation probability is

Mass number counts

Neutron multiplicity distribution

Neutron Multiplicity not corrected for ε

Conclusions