The eikonal approximation(EA)is widely used in various high-energy scattering problems.In this work we generalize this approximation from the scattering problems with time-independent Hamiltonian to the ones with peri...The eikonal approximation(EA)is widely used in various high-energy scattering problems.In this work we generalize this approximation from the scattering problems with time-independent Hamiltonian to the ones with periodical Hamiltonians,i.e.,the Floquet scattering problems.We further illustrate the applicability of our generalized EA via the scattering problem with respect to a shaking spherical square-well potential,by comparing the results given by this approximation and the exact ones.The generalized EA we developed is helpful for the research of manipulation of high-energy scattering processes with external field,e.g.the manipulation of atom,molecule or nuclear collisions or reactions via strong laser fields.展开更多
Relativistic microscopic optical potentials(RMOPs)were constructed for nucleon-nucleus scattering within the framework of relativistic impulse approximation(RIA).Nuclear matter densities were calculated using relativi...Relativistic microscopic optical potentials(RMOPs)were constructed for nucleon-nucleus scattering within the framework of relativistic impulse approximation(RIA).Nuclear matter densities were calculated using relativistic mean-field(RMF)theory,employing both the density-dependent meson-exchange(DD-ME2)and point-coupling(DD-PC1)parameterizations.The resulting RMOP comprised real and imaginary scalar and vector components.Its efficacy was evaluated through a systematic analysis of elastic proton scattering from seven nuclei(^(12)C,^(16)O,^(28)Si,^(40)Ca,^(58)Ni,^(90)Zr,and ^(208)Pb)and calcium isotopes(^(42,44,48)Ca)at incident energies of 200–800 MeV using the Dirac optical model.The RMF-derived densities showed good agreement with experimental root-mean-square radii,neutron skin thicknesses,and binding energies.Differences between the two parameterizations were minimal and diminished for heavier nuclei.The folded potentials displayed characteristic energy-dependent behavior:the real part transitioned from attractive to repulsive,whereas the imaginary absorption strengthened with increasing energy.The differential cross sections calculated using RMOPs showed strong agreement with experimental data.For calcium isotopes,the calculated isotopic trends in neutron skins and densities yielded excellent agreement with cross-section data at 800 MeV.However,the analyzing powers for the neutron-rich ^(48)Ca exhibited some discrepancies.Furthermore,eikonal approximation was employed to compute differential cross sections.This approach incorporated effective central and spin-orbit terms derived from the RMF-based RMOP,providing strong validation of the potential and highlighting the significance of the spin-orbit contribution.It also successfully extended the application of the RMOP to eikonal formalism.展开更多
基金supported by the National Key Research and Development Program of China (Grant No.2022YFA1405300)the Innovation Program for Quantum Science and Technology (Grant No.2023ZD0300700)。
文摘The eikonal approximation(EA)is widely used in various high-energy scattering problems.In this work we generalize this approximation from the scattering problems with time-independent Hamiltonian to the ones with periodical Hamiltonians,i.e.,the Floquet scattering problems.We further illustrate the applicability of our generalized EA via the scattering problem with respect to a shaking spherical square-well potential,by comparing the results given by this approximation and the exact ones.The generalized EA we developed is helpful for the research of manipulation of high-energy scattering processes with external field,e.g.the manipulation of atom,molecule or nuclear collisions or reactions via strong laser fields.
文摘Relativistic microscopic optical potentials(RMOPs)were constructed for nucleon-nucleus scattering within the framework of relativistic impulse approximation(RIA).Nuclear matter densities were calculated using relativistic mean-field(RMF)theory,employing both the density-dependent meson-exchange(DD-ME2)and point-coupling(DD-PC1)parameterizations.The resulting RMOP comprised real and imaginary scalar and vector components.Its efficacy was evaluated through a systematic analysis of elastic proton scattering from seven nuclei(^(12)C,^(16)O,^(28)Si,^(40)Ca,^(58)Ni,^(90)Zr,and ^(208)Pb)and calcium isotopes(^(42,44,48)Ca)at incident energies of 200–800 MeV using the Dirac optical model.The RMF-derived densities showed good agreement with experimental root-mean-square radii,neutron skin thicknesses,and binding energies.Differences between the two parameterizations were minimal and diminished for heavier nuclei.The folded potentials displayed characteristic energy-dependent behavior:the real part transitioned from attractive to repulsive,whereas the imaginary absorption strengthened with increasing energy.The differential cross sections calculated using RMOPs showed strong agreement with experimental data.For calcium isotopes,the calculated isotopic trends in neutron skins and densities yielded excellent agreement with cross-section data at 800 MeV.However,the analyzing powers for the neutron-rich ^(48)Ca exhibited some discrepancies.Furthermore,eikonal approximation was employed to compute differential cross sections.This approach incorporated effective central and spin-orbit terms derived from the RMF-based RMOP,providing strong validation of the potential and highlighting the significance of the spin-orbit contribution.It also successfully extended the application of the RMOP to eikonal formalism.
