One-nucleon-transfer reactions induced by 352-MeVO18onSi

Abstract

The one-nucleon transfer reactions 2 Si("0, "O)29Si and 'Si("0,'9F)~A1 have been studied at 352 MeV bombarding energy. Several strong transitions were identified in each reaction and analyzed using the distorted-wave Born approximation. A shallow, surface-transparent optical potential of E-18 type did not give acceptable results, but deeper, more conventional potentials fitted the data without any need for renormalization.Data on the same reactions taken earlier at 56 MeV were reanalyzed and the results compared to the present experiment. The use of the distorted-eaves approximation is examined critically.

One-nucleon stripping reactions to discrete levels induced by a 793 MeV16O beam on a208Pb target

“…Thus, it has turned out that calculated cross sections and relative spectroscopic factors given both by the EFR-DWBA formalism are rather independent of depths of the strong absorption potentials. As expected, surface transparent potentials such as E-18 family of [4] produce much higher values for the DWBA cross sections which induce then worth results for the normalization factors. It is worthwhile to note that the 50 MeV deep optical model family of our EFR-DWBA analysis seems to be the one which has its parameter values the most in agreement with the theoretical predictions of the energy density formalism used with the sudden approximation [15,16].…”

“…This EFR-DWBA analysis reproduces quite well the relative intensities of all the single particle states as it can be judged from the spectroscopic factors listed on Table 1. They can be compared with the values obtained at lower incident energy 1-3] and also with the ones given by light ion induced reactions [1][2][3][4][5][6][7][8][9][10][11][12]. The theoretical spectroscopic factors are the results of a quasi-particle calculation, see Ref.…”

“…1 which allows to reproduce the elastic scattering data. In order to investigate if the normalization factor is dependent of the real-potential depth value as it may be suggested from the results of the DWBA analysis of [4], we have tried a much deeper potential defined by the following values: V= W=200 MeV, roc=ro=ri=O.8985 fm, and a=ai=O.8575 fm. The elastic scattering fit of this potential is the very same of the one of Fig.…”

“…These latter reactions are well governed by semiclassical selection rules and are well described by the one-step Exact-Finite-Range Distorted Wave Born Approximation (EFR-DWBA) Ref. 1 when one is concerned only with relative spectroscopic factors [2][3][4]. On the other hand the prediction of absolute cross section values is still an unresolved problem [3].…”

“…In order to understand the dynamics of direct surface transfer reactions induced by heavy ions, one-nucleon * Experiment performed at the GANIL National Laboratory, France stripping reactions have been extensively studied [- [1][2][3][4]. These latter reactions are well governed by semiclassical selection rules and are well described by the one-step Exact-Finite-Range Distorted Wave Born Approximation (EFR-DWBA) Ref.…”