Nucleon exchange mechanism in heavy-ion collisions at near-barrier energies

Yilmaz, B.; Ayık, S.; Lacroix, Denis; Washiyama, Kouhei

doi:10.1103/physrevc.83.064615

Cited by 45 publications

(57 citation statements)

References 30 publications

(48 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[13], in small amplitude limit, that this approach gives rise to the same expression for dispersions of one-body observables as the one obtained in the variational description of Balian and Vénéroni (BV) [14,15]. In other applications, the average version of SMF theory was recently employed [16][17][18] to successfully reconcile onset of dissipation in TDHF and to calculate transport coefficients for relative momentum and nucleon-exchange in deep-inelastic heavy-ion collisions [19].…”

mentioning

confidence: 97%

Symmetry breaking and fluctuations within stochastic mean-field dynamics: Importance of initial quantum fluctuations

2012

View full text Add to dashboard Cite

Dynamics of spontaneous symmetry breaking and fluctuations in the Lipkin-Meshkov-Glick model are investigated in a stochastic mean-field approach. Different from the standard mean-field, in the stochastic approach, initial state fluctuations, are incorporated. In weak coupling, the approach perfectly reproduces the exact quantal dynamics. On the other hand, for increasing coupling strength, above the symmetry breaking threshold, the approach provides description of gross properties (i.e. time averaged behavior) of the exact quantal evolution.

show abstract

mentioning

confidence: 97%

Symmetry breaking and fluctuations within stochastic mean-field dynamics: Importance of initial quantum fluctuations

2012

View full text Add to dashboard Cite

show abstract

“…These distribution have zero mean values δv λ p (t) = 0, δv λ n (t) = 0 and their variances in Markovian approximation are determined by [14][15][16][17] …”

Section: Diffusion Mechanismmentioning

confidence: 99%

“…We take x-axis as the collision direction and the position x 0 (t) of the window plane is determined from the TDHF calculations. As described in [14][15][16][17], the local density is projected on the reaction plane and the window is located at the lowest density plane on the neck at each time step. According to the SMF approach, the proton and neutron numbers of the projectile-like fragment follows a stochastic evolution according to the following Langevin equations,…”

Section: Diffusion Mechanismmentioning

confidence: 99%

Multinucleon exchange in quasifission reactions

2015

Self Cite

View full text Add to dashboard Cite

Nucleon exchange mechanism is investigated in the central collisions of 40 Ca + 238 U and 48 Ca + 238 U systems near the quasi-fission regime in the framework of the Stochastic Mean-Field (SMF) approach. Sufficiently below the fusion barrier, di-nuclear structure in the collisions is maintained to a large extend. Consequently, it is possible to describe nucleon exchange as a diffusion process familiar from deep-inelastic collisions. Diffusion coefficients for proton and neutron exchange are determined from the microscopic basis of the SMF approach in the semi-classical framework. Calculations show that after a fast charge equilibration the system drifts toward symmetry over a very long interaction time. Large dispersions of proton and neutron distributions of the produced fragments indicate that diffusion mechanism may help to populate heavy trans-uranium elements near the quasi-fission regime in these collisions.

show abstract

“…Furthermore, the CoMD model, at variance with mean-field models, naturally takes into account nucleon-nucleon correlations that are of vital importance for the description of observables involving fluctuations, as for example the nucleon transport in peripheral collisions as in the present work. (We remind that in meanfield transport models, effects beyond the mean field are simulated via nucleon-nucleon collisions, as well as fluctuations of the mean field [51,53].) For these reasons, the CoMD predictions are especially valuable for the interpretation of the results of the present study.…”

Section: Description Of the Theoretical Modelsmentioning

confidence: 99%

“…More sophisticated microscopic approaches have also been adopted including semiclassical mean-field transport models of Boltzmann-type such as BUU (BoltzmannUehling-Ulenbeck) [9,31,48,49], BNV (BoltzmannNordheim-Vlasov) [11,50], SMF (Stochastic Mean Field) [11,51] and the fully quantal TDHF (time-dependent Hartree-Fock) approach [52][53][54]. Furthermore, N-body approaches of Quantum Molecular Dynamics (QMD) type [55] have been applied such as the Constrained Molecular Dynamics (CoMD) model [56,57] employed in this work.…”

Section: Introductionmentioning

confidence: 99%

Isoscaling of heavy projectile residues andN/Zequilibration in peripheral heavy-ion collisions below the Fermi energy

et al. 2014

View full text Add to dashboard Cite

The isoscaling of heavy projectile residues from peripheral heavy-ion reactions at 15-25 MeV/nucleon is employed to obtain information on the process of N/Z equilibration. Recent mass spectrometric data of projectile residues from the reactions of 86 Kr (15 MeV/nucleon) with 64,58 Ni and 124,112 Sn were first analyzed. The isotopically resolved yield distributions of the fragments in the range Z=26-39 were employed for the isoscaling analysis. The yield ratios R21(N,Z) of the fragments from each pair of systems exhibit isoscaling (i.e. an exponential dependence on the fragment neutron number N for each atomic number Z) with the isoscaling parameter α increasing with decreasing (or increasing) Z away from the projectile. This variation is related to the evolution toward N/Z equilibration with increasing energy dissipation estimated from the residue velocities. In parallel to the new heavy-residue isoscaling data of 86 Kr at 15 MeV/nucleon, our previous data at 25 MeV/nucleon for the reactions 86 Kr+ 124,112 Sn and 64 Ni+ 64,58 Ni, 64 Ni+ 124,112 Sn, as well as our data at 15 MeV/nucleon of the lighter system 40 Ar+ 64,58 Ni were analyzed in a similar way. Calculations with the stochastic nucleon-exchange model DIT (Deep Inelastic Transfer) and the microscopic many-body model CoMD (Constrained Molecular Dynamics) provided an overall fair description of data and valuable guidance for their interpretation. Interestingly, the data of the 86 Kr+Ni,Sn reactions at 15 MeV/nucleon show a retardation of the process of N/Z equilibration which, as suggested by the CoMD calculations, is indicative of the collective character of the process. This retardation is not present in the investigated systems at 25 MeV/nucleon (and the light 40 Ar+Ni systems at 15 MeV/nucleon), whose behavior is found to be consistent with stochastic nucleon exchange.

show abstract

Nucleon exchange mechanism in heavy-ion collisions at near-barrier energies

Cited by 45 publications

References 30 publications

Symmetry breaking and fluctuations within stochastic mean-field dynamics: Importance of initial quantum fluctuations

Symmetry breaking and fluctuations within stochastic mean-field dynamics: Importance of initial quantum fluctuations

Multinucleon exchange in quasifission reactions

Isoscaling of heavy projectile residues andN/Zequilibration in peripheral heavy-ion collisions below the Fermi energy

Contact Info

Product

Resources

About