Real and imaginary parts of the microscopic optical potential between nuclei in the sudden and adiabatic approximation and its application to medium energy 12C-12C scattering

doi:10.1016/0375-9474(87)90364-2

Nuclear Physics A

Volume 465, Issue 3, 13 April 1987, Pages 550-572

https://doi.org/10.1016/0375-9474(87)90364-2 Get rights and content

Abstract

Real and imaginary parts of the optical potential between two nuclei have been calculated from the realistic two-nucleon interaction of Reid using the approach of Faessler and collaborators but with the following modifications: (a) A surface curvature term proportional to the square of the gradient of the density has been added to the energy density functional and the parameters are determined so as to reproduce the binding energies and rms radii of nuclei considered and (b) in addition to the sudden approximation, an adiabatic situation is also considered. Whereas, in the sudden approximation the density of the composite system is obtained by adding the densities of the two colliding nuclei, in the adiabatic approximation, the maximum density in the composite system is limited to the saturation value while conserving the nucleon number. Although the real part of the potential is in the center quite different in these two approximations, the cross sections are not. The real and imaginary parts of the optical potential are calculated for the nuclear pairs ¹²C+¹²C, ¹⁶O+¹⁶O, ⁴⁰Ca+⁴⁰Ca and ²⁰⁸Pb+²⁰⁸Pb for relative momenta per nucleon k_r = 0 and 1 fm⁻¹. Elastic, inelastic and reaction cross sections are calculated for ¹²C+¹²C scattering at E_lab = 300, 360 and 1016 MeV using the calculated potential and coupling the elastic channel to the 2⁺ at 4.44 MeV and 3⁻ at 9.64 MeV, and compared with the experimental data. The agreement with the data at 1016 MeV is satisfactory and the theory can also reproduce the general trend of the angular distributions at 300 and 360 MeV but the calculated values at larger angles overestimate the data. The energy dependence and the magnitude of the observed reaction cross section are well reproduced by the theory.

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^☆: Supported by the Gesellschaft für Schwerionenforschung, Darmstadt and the Deutsche Forschungsgemeinschaft.

¹: Permanent address: Physics Dept, Southern Illinois University, Carbondale, Illinois 62901, USA.

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Real and imaginary parts of the microscopic optical potential between nuclei in the sudden and adiabatic approximation and its application to medium energy 12C-12C scattering☆

Abstract

Nucl. Phys.

Nucl. Phys.

Nucl. Phys.

Nucl. Phys.

Phys. Rev.

Phys. Rev.

At. Data and Nucl. Data Tables

Nucl. Phys.

Phys. Lett.

Nucl. Phys.

Phys. Rev.

Phys. Rev.

Phys. Rev. Lett.

Phys. Lett.

Real and imaginary parts of the microscopic optical potential between nuclei in the sudden and adiabatic approximation and its application to medium energy ¹²C-¹²C scattering☆