Optical model studies of 6Li elastic scattering at 156 MeV

Abstract

Größen bestimmen, wird diskutiert.-1 -

Investigation of the sequential break-up mode6Li?6Li*(31 +)??+d of 156 MeV6Li projectiles on208Pb in the very forward angular hemisphere

“…3. The best fit curve reproduces quite well the data, even in some detailed structure by a slight modification of the nuclear potential given in [23] (Table 1). The Coulomb deformation parameter tic (of a realistic Fermi shaped charge distribution) corresponds to the reduced electromagnetic probability B (E2) = 18.1 e 2 fm 4 which is close to the value B(E2) = 21.8 _+ 4.8 e 2 fm 4 from inelastic electron scattering [21], and it is accompanied by the isoscalar value B (I2) = 19.2 e 2 fm 4 of the nuclear excitation.…”

“…The optical potential has been parametrized by the WoodsSaxon form of the real (Vo, rv, av) and imaginary (Wo, rw, aw) parts (only volume absorption), neglecting a possible spin-orbit interaction. In general, starting with parameter values given in [23] for 156 MeV 6Li scattering on 2~ the parameters of the extended optical potential (including the values of/3N) have been adjusted, in addition to parameters of the deformed Coulomb potential, by fitting simultaneously the elastic and the projectile excitation cross sections through minimizing the Z2-value. A correct treatment of the excitation by the long-range Coulomb potential (whose form factors have to approach a 1/r L+ 1-dependence for large distances r) implied a detailed study of numerical convergence, in order to avoid nonphysical structures of the cross sections at small angles.…”

Long range absorption in the scattering of 6He on 208Pb and 197Au at 27 MeV

“…The optical model parameters used are given in figure 2 we present the "averaged data" measured for the collision of 6 He on 197 Au and 208 Pb at 27 MeV bombarding energy. The solid lines are the global optical model calculations which uses Cook potential [16]. These calculations, that do not take into account the effect of dipole polarizability, show a well defined rainbow around 43 degrees, which is clearly absent from the experimental data.…”

Investigation of Coulomb dipole polarization effects on reactions involving exotic nuclei

“…The mean field potential, called optical potential (OP), has a real part that represents the bare interaction and an imaginary part that simulates the absorption of flux from the elastic channel due to reaction processes [3][4][5].…”

“…Either for older stable nuclei reaction data [3] or recent exotic nuclei ones [4,5], it is commonly assumed the OP with a parametrized Woods-Saxon (WS) form, to represent the strength and geometry of the potentials as a function of the interacting distance.…”