Combined method to extract spectroscopic information

Spectroscopic factors (SFs) play an important role in nuclear physics and astrophysics. The traditional method of extracting SFs from direct transfer reactions suffers from serious ambiguities. We discuss a modified method that is based on including the asymptotic normalization coefficient of the overlap functions into the transfer analysis. In the modified method the contribution of the external part of the reaction amplitude, typically dominant, is fixed and the SF is determined from the fitting of the internal part. We illustrate the modified method with $(d,p)$ reactions on ${}^{208}\mathrm{Pb},{}^{12}\mathrm{C}$, and ${}^{84}\mathrm{Se}$ targets at different energies. The modified method allows one to extract the SFs, which do not depend on the shape of the single-particle nucleon-target interaction, and has the potential of improving the reliability and accuracy of the structure information. This is specially important for nuclei on dripline, where not much is known.

Figure 1

Cross section for ${}^{208}\mathrm{Pb}(d,p){}^{209}\mathrm{Pb}$ (ground state) at 22 MeV and the dependence on the single-particle parameters: experimental value (solid line), experimental error bar (shaded area), and the DWBA prediction (dot-dashed curve).

Figure 2

Cross section for ${}^{12}\mathrm{C}(d,p){}^{13}\mathrm{C}$ (ground state) at 51 MeV and the dependence on the single-particle parameters: experimental value (solid line), experimental error bar (shaded area), and the DWBA prediction (dot-dashed curve).