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DOE OSTI · 21499190

Fragmentation paths in dynamical models

Colonna, M·Rizzo, J·Ono, A
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Abstract

We undertake a quantitative comparison of multifragmentation reactions, as modeled by two different approaches: the antisymmetrized molecular dynamics (AMD) and the momentum-dependent stochastic mean-field (SMF) model. Fragment observables and pre-equilibrium (nucleon and light cluster) emission are analyzed, in connection with the underlying compression-expansion dynamics in each model. Considering reactions between neutron-rich systems, observables related to the isotopic properties of emitted particles and fragments are also discussed, as a function of the parametrization employed for the isovector part of the nuclear interaction. We find that the reaction path, particularly the mechanism of fragmentation, is different in the two models and reflects on some properties of the reaction products, including their isospin content. This should be taken into account in the study of the density dependence of the symmetry energy from such collisions.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSBARYONSCALCULATION METHODSCOLLISIONSCOMPARATIVE EVALUATIONSCOMPRESSIONDENSITYELEMENTARY PARTICLESEMISSIONEQUILIBRIUMEVALUATIONEXPANSIONFERMIONSHADRONSINTERACTIONSISOSPINISOVECTORSMEAN-FIELD THEORYMOLECULAR DYNAMICS METHODNEUTRONSNUCLEAR FRAGMENTATIONNUCLEAR REACTIONSNUCLEONSPARTICLE PROPERTIESPARTICLESPHYSICAL PROPERTIESSIMULATIONSTOCHASTIC PROCESSESSYMMETRYTENSORSVECTORS

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Colonna, M, Rizzo, J, Ono, A. 2010-11-15. Fragmentation paths in dynamical models. https://doi.org/10.1103/physrevc.82.054613

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