A parameter-free optical potential for the heavy-ion elastic scattering process

Abstract

Thirty elastic scattering angular distributions for seven heavy-ion systems, in wide energy ranges, have been studied with the aim of systematizing the optical potential, real and imaginary parts, in a global way. The framework is: i) an extensive systematization of nuclear densities, ii) the energy dependence of the bare potential accounted by a model based on the nonlocal nature of the interaction, and iii) the real and imaginary parts of the optical potential assumed to have the same radial shape.

Consistent analysis of fusion data without adjustable parameters for a wide variety of heavy-ion systems

“…The SP potential has been successful in describing the elastic scattering and peripheral reaction 044606-2 channels for several heavy-ion systems in a very wide energy region [18,[20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35]. In the present work, we use the SP interaction generalized for deformed nuclei [37,38].…”

“…The analyses are performed in the context of the ZPM model and using the São Paulo (SP) potential [17][18][19] as the bare interaction. The SP potential has been successful in describing the elastic scattering and peripheral reaction channels for several systems in a wide energy region, from sub-barrier to intermediate energies [18,[20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35]. Therefore, the bare interaction assumed here to analyze the fusion data is also appropriate to describe the elastic scattering process.…”

“…Since such combinations always exist, independently of shell closures, little structure is observed in β 3 . Figure 7 presents systems that involve 28 Si as projectile. Figures 8-10 show systems with 32,36 S. Figures 11, 12, and 13 correspond to systems involving 40,48 Ca and 40 Ar.…”

Non-local effects on the heavy-ion fusion at sub-barrier energies

“…The São Paulo potential (SPP) has been in use for about one decade, especially in the analysis of heavy-ion elastic scattering data [9,[11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]. It is based in part on the idea of single folding employed for alpha-nucleus scattering by Jackson and Johnson [27] in order to get the Perey-Buck (PB) nonlocal effects [28] extended to heavy ions.…”

“…Of course, when used in coupled-channel calculations, the non-locality is transformed into a non-dispersive energy dependence. In so far as the Pauli non-locality is concerned, the resulting locally equivalent nondispersive energy dependent potential has been constructed by our group [8][9][10][11] and it is coined the São Paulo potential. We shall use this potential here to investigate the relevance of the Pauli, exchange, non-locality on the fusion cross section at energies around the barrier.…”