Quantal Diffusion in Heavy-Ion Collisions

Year 2019, NSP2018 Special Issue, 195 - 200, 28.03.2019

Osman Yılmaz , Bülent Yılmaz Şakir Ayık

Abstract

We investigate the quasi-fission reactions in the basis on the
Stochastic Mean-Filed (SMF) approach that provides a microscopic 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.

Keywords

Multinucleon transfer, quasi-fission reaction, stochastic mean-field theory

References

• C. Simenel, Particle-Number Fluctuations and Correlations in Transfer Reactions Obtained Using the Balian-Ve´ne´roni Variational Principle, Phys. Rev. Lett. 106, 112502 (2011).
• V. E. Oberacker, A. S. Umar, and C. Simenel, Dissipative dynamics in quasifission, Phys. Rev. C 90, 054605 (2014).
• K. Sekizawa and K. Yabana, Time-dependent Hartree-Fock calculations for multinucleon transfer and quasifission processes in the 64Ni + 238U reaction, Phys. Rev. C 93, 054616 (2016).
• S. Ayik, A stochastic mean-field approach for nuclear dynamics, Phys. Lett. B 658, 174 (2008).
• S. Ayik, B. Yilmaz, O. Yilmaz, A. S. Umar, and G. Turan, Multinucleon transfer in central collisions of 238U + 238U, Phys. Rev. C 96, 024611 (2017).
• S. Ayik, B. Yilmaz, O. Yilmaz, and A. S. Umar, Quantal diffusion description of multinucleon transfers in heavy-ion collisions, Phys. Rev. C 97, 054618 (2018).
• B. Yilmaz, S. Ayık, O. Yilmaz and A. S. Umar, Multinucleon reactions in 58Ni+60Ni and 58Ni+60Ni in a stochastic mean-field approach, Phys. Rev. C 98, 034604 (2018).
• J. Y. Roynette, et. al., On the time scale of 40 Ca+40Ca strongly damped reactions, Phys Lett B67, 395 (1977).
• E. Williams et. al., Exploring zeptosecond quantum equilibration dynamics: from Deep-inelastic to fusion-fission outcomes in 58Ni+60Ni reactions, Phys. Rev. Lett. 120, 022501 (2018).
• E. M. Kozulin, et. al., Shell effects in fission, quasi-fission and multinucleon transfer reaction, J. Phys, Conf. Ser. 515, 012010 (2014).