V. D. Toneev

Cascade-exciton model of nuclear reactions

Abstract An approach combining essential features of the exciton and intranuclear cascade models is developed. The cascade-exciton model predictions for the energy spectra, angular distributions and double differential cross sections of nucleons and complex particles as well as for the excitation functions are analyzed at incident nucleon energies T 0 ≲ 100 MeV and in a large range of nuclear target masses. We discuss the relative role of different interaction mechanisms and their possible experimental identification.

Particle emission in light and heavy ion reactions

Abstract Physical effects arising from heavy ion-induced reactions as opposed to light ion-induced reactions are discussed in the framework of the cascade model. Our approach is shown to be suitable for the study of collective effects due to nuclear matter compression.

Dynamics of relativistic heavy-ion collisions

Abstract A dynamical model of independent quark-gluon strings is applied to relativistic collisions of heavy ions. Fairly well agreement with recent results of the CERN experiments is achieved and contributions of different nuclear effects are disentangled. Estimates of energy density reached in central heavy ion collisions are given. A possible manifestation of collective effects for string-string interactions (colour rope formation) is discussed.

A cascade-evaporation model for photonuclear reactions

Abstract Detailed and systematic Monte Carlo calculations have been performed for different characteristics of inelastic photonuclear reactions for an energy range of Tγ ≈ 50 MeV–1 GeV in the framework of the intranuclear cascade model taking into account the competition between particle evaporation and fission of excited residual nuclei. The calculated results agree well with experimental data. On the basis of the data listed it is possible to extrapolate the corresponding characteristics for intermediate energies and nuclei.

Mass transport and dynamics of the relative motion in deeply inelastic heavy-ion collisions

Abstract We investigate the mass transport in deeply inelastic heavy-ion collisions on the basis of a Kokker-Planck equation. Mass diffusion and drift coefficients are taken from a microscopic model. The mean interaction time is calculated dynamically in a solution of the classical equations of motion. To account for deformations of the fragments we modify the nuclear potential in the exit channel. Theoretical element distributions for 132Xe (5.9 MeV/nucleon) + 120Sn and 238U (7.42 MeV/ nucleon) + 238U are compared with the data and the remaining discrepancies are discussed. Including statistical fluctuations in the relative motion we calculate various multidifferential cross sections which allow for a detailed test of the model.

Examination of the directed flow puzzle in heavy-ion collisions

Recent STAR data for the directed flow of protons, antiprotons, and charged pions obtained within the beam energy scan program are analyzed within the parton-hadron-string-dynamics (PHSD and HSD) transport models and a 3-fluid hydrodynamics approach. Both versions of the kinetic approach, HSD and PHSD, are used to clarify the role of partonic degrees of freedom. The PHSD results, simulating a partonic phase and its coexistence with a hadronic one, are roughly consistent with data. The hydrodynamic results are obtained for two equations of state (EoS), a pure hadronic EoS and an EoS with a crossover type transition. The latter case is favored by the STAR experimental data. Special attention is paid to the description of antiproton directed flow based on the balance of

Lattice QCD constraints on the nuclear equation of state

p\overline{p}

Anisotropy of dilepton emission from nuclear collisions

annihilation and the inverse processes for

Fission and decay of excited nuclei

p\overline{p}

Non-Markovian effects in strong-field pair creation

pair creation from multimeson interactions. Generally, the semiqualitative agreement between the measured data and the model results supports the idea of a crossover type of quark-hadron transition that softens the nuclear EoS but shows no indication of a first-order phase transition.