Study of the rainbow-like pattern in the elastic scattering of¹⁶O on²⁷Al at<i>E</i>_lab.= 100 MeV

Abstract

Recently, a rainbow pattern in the elastic scattering of 16O + 27Al at Elab. = 100 MeV was reported. In the present paper, we show that the predicted change of slope of the cross section, as a function of angle, is mostly due to the far-side component of the scattering, which is affected by the inelastic couplings. The experimental data is consistent with the calculations up to the inflection point, where the effect of the couplings is significant. New experimental data, in very good agreement with the theoretical expectations around the Coulomb rainbow angle, are also presented.