Theoretical modeling of nucleus-nucleus collisions is often based on the nucleus-nucleus potential.One of the advanced methods for constructing this potential is the semi-microscopical double-folding model with M3 YPa...Theoretical modeling of nucleus-nucleus collisions is often based on the nucleus-nucleus potential.One of the advanced methods for constructing this potential is the semi-microscopical double-folding model with M3 YParis NN-forces.Proton and neutron densities are significant components of this model.The correct nucleon density(ND) must reproduce the experimental nuclear charge density(NCD).However,those who deal with modeling the fusion process typically disregard this circumstance.We aim to achieve a good description of both the nuclear charge density and above-barrier fusion cross sections of even-even light nuclei with Z=N.We consider several versions of NDs available in literature and construct our own approximation for the ND of the even-even spherical nuclei^(12)C,^(16)O,and^(40)Ca,abbreviated as FE-density(Fermi+exponential).We carefully compare the NCDs resulting from different versions of NDs with the experimental NCDs.After finding the nucleus-nucleus potential using the double-folding model with the density dependent M3 Y-Paris NN-forces and FE densities,we evaluate the abovebarrier fusion cross sections for five reactions,^(12)C+^(12)C,^(12)C+^(16)O,^(16)O+^(16)O,^(16)O+^(40)Ca,and^(40)Ca+^(40)Ca,and40Ca+40Ca,for which experimental data are available.The cross sections are calculated using two approaches:a) the barrier penetration model and b) the trajectory model with surface friction(TM).To find the transmission coefficients for the TM,the Langevin equations are employed.For all considered reactions,our TM typically reproduces the above-barrier experimental cross sections within 10-15%.The only adjustable parameter of the model,the optimal friction strength KRm,is found to be approximately 90 zs·GeV-1for the light reactions12C+12C,12C+16O,and16O+16O and approximately 15zs·GeV-1for the heavy reactions16O+40Ca and40Ca+40Ca.The latter findings are in reasonable agreement with the systematics found previously.Thus,the FE-recipe allows highly accurate and simultaneous reproduction of both the nuclear charge density and above-barrier fusion cross sections of five reactions involving12C,160,and40Ca nuclei.展开更多
基金Supported by the Foundation for the Advancement of Theoretical Physics and Mathematics“BASIS.”。
文摘Theoretical modeling of nucleus-nucleus collisions is often based on the nucleus-nucleus potential.One of the advanced methods for constructing this potential is the semi-microscopical double-folding model with M3 YParis NN-forces.Proton and neutron densities are significant components of this model.The correct nucleon density(ND) must reproduce the experimental nuclear charge density(NCD).However,those who deal with modeling the fusion process typically disregard this circumstance.We aim to achieve a good description of both the nuclear charge density and above-barrier fusion cross sections of even-even light nuclei with Z=N.We consider several versions of NDs available in literature and construct our own approximation for the ND of the even-even spherical nuclei^(12)C,^(16)O,and^(40)Ca,abbreviated as FE-density(Fermi+exponential).We carefully compare the NCDs resulting from different versions of NDs with the experimental NCDs.After finding the nucleus-nucleus potential using the double-folding model with the density dependent M3 Y-Paris NN-forces and FE densities,we evaluate the abovebarrier fusion cross sections for five reactions,^(12)C+^(12)C,^(12)C+^(16)O,^(16)O+^(16)O,^(16)O+^(40)Ca,and^(40)Ca+^(40)Ca,and40Ca+40Ca,for which experimental data are available.The cross sections are calculated using two approaches:a) the barrier penetration model and b) the trajectory model with surface friction(TM).To find the transmission coefficients for the TM,the Langevin equations are employed.For all considered reactions,our TM typically reproduces the above-barrier experimental cross sections within 10-15%.The only adjustable parameter of the model,the optimal friction strength KRm,is found to be approximately 90 zs·GeV-1for the light reactions12C+12C,12C+16O,and16O+16O and approximately 15zs·GeV-1for the heavy reactions16O+40Ca and40Ca+40Ca.The latter findings are in reasonable agreement with the systematics found previously.Thus,the FE-recipe allows highly accurate and simultaneous reproduction of both the nuclear charge density and above-barrier fusion cross sections of five reactions involving12C,160,and40Ca nuclei.
