Eur. Phys. J. A (2016) 52: 169
https://doi.org/10.1140/epja/i2016-16169-y

Regular Article - Experimental Physics

Interplay of the elastic and inelastic channels in the ¹⁶O+²⁷Al scattering at E_lab = 280 MeV

¹ Dipartimento di Fisica e Astronomia Università di Catania, I-95125, Catania, Italy
² INFN, Laboratori Nazionali del Sud, I-95125, Catania, Italy
³ Instituto de Fısica, Universidade Federal Fluminense, 24210-346, Niterói, RJ, Brazil
⁴ Instituto de Física, Universidade de São Paulo, DFN, C.P. 66318, 05314-970, São Paulo, SP, Brazil
⁵ INFN, Sezione di Catania, via S. Sofia, 64, I-95125, Catania, Italy

^* e-mail: rlinares@if.uff.br

Received: 26 January 2016
Revised: 27 April 2016
Accepted: 4 May 2016
Published online: 24 June 2016

Abstract

Recent data indicated a nuclear rainbow-like pattern in the elastic scattering of ¹⁶O + ²⁷Al at MeV that arises from couplings of the ground to the low-lying states of the ²⁷Al nucleus. Similar effect was identified in the elastic angular distribution of ¹⁶O + ¹²C at and 330 MeV. These experiments show a crucial role of microscopic details of nuclear structure in the elastic scattering of heavy ions at energies well above the Coulomb barrier. In this work we investigate the ¹⁶O + ²⁷Al system at MeV for which a coupled channel calculation predicts a pronounced nuclear rainbow-like structure. Obtained experimental data show evidences of an important coupling of the elastic channel to the inelastic. Coupled channel calculations reproduce the experimental angular distributions when a re-normalization factor on the real part of the optical potential is introduced. A proper theoretical approach still requires a high degree of accuracy for the nuclear structure models and new tools to deal with collective excitations.