Quantal diffusion in heavy-ion collisions

We investigate the quasi-fission reactions in the basis on the Stochastic Mean-Filed (SMF) approach that provides amicroscopic and quantal description of the multi-nucleon exchange mechanism. In deep-inelastic heavy-ion collisions, colliding ions stick and move together for a long time. During this contact time many nucleons exchange between projectile and target nuclei, and the composite system then separate in two main primary fragments without forming a compound nucleus. Quasi-fission is a non-compound nuclear process in deep-inelastic heavy-ion collisions and the multi-nucleon exchange mechanism in the quasi-fission reactions is important. We calculate the quantal transport coefficients for heavy-ion collisions at bombarding energies below their fusion barriers and determine the primary fragment mass distributions. Quantal calculations are compared with the experimental data.
XI. International Conference on Nuclear Structure Properties 12 - 14 Ekim 2018


Quantal diffusion description of multinucleon transfers in heavy-ion collisions
Ayik, S.; Yilmaz, B.; Yılmaz, Osman; Umar, A. S. (2018-05-29)
Employing the stochastic mean-field (SMF) approach, we develop a quantal diffusion description of the multi-nucleon transfer in heavy-ion collisions at finite impact parameters. The quantal transport coefficients are determined by the occupied single-particle wave functions of the time-dependent Hartree-Fock equations. As a result, the primary fragment mass and charge distribution functions are determined entirely in terms of the mean-field properties. This powerful description does not involve any adjustab...
Quantal description of nucleon exchange in a stochastic mean-field approach
Ayik, S.; YILMAZ TÜZÜN, ÖZGÜL; YILMAZ, BÜLENT; Umar, A. S.; GÖKALP, AHMET; Turan, Gürsevil; Lacroix, D. (2015-05-04)
The nucleon exchange mechanism is investigated in central collisions of symmetric heavy ions in the basis of the stochastic mean-field approach. Quantal diffusion coefficients for nucleon exchange are calculated by including non-Markovian effects and shell structure. Variances of fragment mass distributions are calculated in central collisions of Ca-40 + Ca-40, Ca-48 + Ca-48, and N-56 i+ Ni-56 systems.
Quantal diffusion approach for multinucleon transfers in Xe plus Pb collisions
Ayik, S.; Yilmaz, B.; Yılmaz, Osman; Umar, A. S. (2019-07-01)
Employing a quantal diffusion description based on the stochastic mean-field approach, we analyze the mass distribution of the primary fragments in the collisions of the Xe-136 + Pb-208 system at the bombarding energy E-c.m. = 526 MeV. This quantal approach provides a good description of the primary fragment distribution without any adjustable parameter, including the effects of shell structure
Quantal description of instabilities in nuclear matter in a stochastic relativistic model
Yılmaz Tüzün, Özgül; Gokalp, A. (2011-10-01)
Spinodal instabilities and early development of density fluctuations are investigated in the stochastic extension of Walecka-type relativistic mean field including non-linear self-interactions of scalar mesons in the quantal framework. Calculations indicate that at low temperatures T = 0-2 MeV, the initial growth of density fluctuations and hence the initial condensation mechanism occur much faster in quantal calculations than those found in the semi-classical framework. However, at higher temperatures T = ...
Quantal diffusion description of isotope production via the multinucleon transfer mechanism in Ca-48+U-238 collisions
Ayik, S.; Arik, M.; Karanfil, E. C.; Yılmaz, Osman; Yilmaz, B.; Umar, A. S. (2021-11-01)
As an extension of previous work, we calculate the production cross section of heavy neutron-rich isotopes by employing the quantal diffusion description to 48Ca+238U collisions. The quantal diffusion is deduced from stochastic mean-field approach, and transport properties are determined in terms of time-dependent single-particle wave functions of the time-dependent Hartree-Fock theory. As a result, the approach allows for prediction of production cross sections without any adjustable parameters. The second...
Citation Formats
O. Yılmaz, “Quantal diffusion in heavy-ion collisions,” Trabzon, Türkiye, 2019, p. 195, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/82835.