Long-range dynamic polarization potentials forBe11projectiles onZn64

Abstract

We investigate the effects of the long-range dynamic polarization (LRDP) potential, which consists of the Coulomb dipole excitation (CDE) potential and the long-range nuclear (LRN) potential, for the $^{11}\mathrm{Be}$ projectile on $^{64}\mathrm{Zn}$. To study these effects, we perform a ${\ensuremath{\chi}}^{2}$ analysis of an optical model including the LRDP potential as well as a conventional short-range nuclear (SRN) potential. To take these effects into account, we argue that both the CDE and LRN potentials are essential to explaining the experimental values of ${P}_{E}$, which is the ratio of the elastic scattering cross section to the Rutherford cross section. The Coulomb and nuclear parts of the LRDP potential are found to contribute to a strong absorption effect. Strong absorption occurs because the real part of the CDE and LRN potentials lowers the barrier, and the imaginary part of the CDE and LRN potentials removes the flux from the elastic channel in the $^{11}\mathrm{Be}+^{64}\mathrm{Zn}$ system. Finally, we extract the total reaction cross section ${\ensuremath{\sigma}}_{R}$ including the inelastic, breakup, and fusion cross sections. The contribution of the inelastic scattering by the first excited state at ${\ensuremath{\varepsilon}}_{\mathrm{x}}^{1\mathrm{st}}=0.32\phantom{\rule{4pt}{0ex}}\mathrm{MeV}\phantom{\rule{4pt}{0ex}}(1/{2}^{\ensuremath{-}})$ is found to be relatively large and cannot be ignored. In addition, our results are shown to agree quite well with the experimental breakup reaction cross section by using a fairly large radius parameter.