R. Linares, M. J. Ermamatov, J. Lubian, F. Cappuzzello, D. Carbone, E. N. Cardozo, M. Cavallaro, J. L. Ferreira, A. Foti, A. Gargano, B. Paes, G. Santagati, V. A. B. Zagatto

Phys. Rev. C 98, 054615

26/11/2018

Abstract

Background: Recently, a systematic exploration of two-neutron transfer induced by the (18O,16O) reaction on different targets has been performed. The high-resolution data have been collected at the MAGNEX magnetic spectrometer of the INFN-LNS Laboratory in Catania and analyzed with the coupled reaction channel (CRC) approach. The simultaneous and sequential transfers of the two neutrons have been considered under the same theoretical framework without the need for adjustable factors in the calculations. Purpose: A detailed analysis of the one-neutron transfer cross sections is important to study the sequential two-neutron transfer. Here, we examine the (18O,17O) reaction on 16O,28Si, and 64Ni targets. These even-even nuclei allow for investigation of one-neutron transfer in distinct nuclear shell spaces. Method: The MAGNEX spectrometer was used to measure mass spectra of ejectiles and extract differential cross sections of one-neutron transfer to low-lying states. We adopted the same CRC formalism used in the sequential two-neutron transfer, including relevant channels and using spectroscopic amplitudes obtained from shell-model calculations. We also compare with the one-step distorted-wave Born approximation (DWBA). Results: For the 18O+16O and the 18O+28O systems, we used two interactions in the shell model. The experimental angular distributions are reasonably well reproduced by the CRC calculations. In the 18O+64Ni system, we considered only one interaction, and the theoretical curve describes the shape and order of magnitude observed in the experimental data. Conclusions: Comparisons between experimental DWBA and CRC angle-integrated cross sections suggest that excitations before or after the transfer of a neutron are relevant in the 18O+16O and 18O+64Ni systems.

10.1103/PhysRevC.98.054615