Resonant suppression of the above-barrier fusion cross-section in ${}^{19}$O + ${}^{12}$C

Abstract

Fusion excitation functions for ${}^{19}$O and ${}^{19}$F + ${}^{12}$C were simultaneously measured along with ${}^{20}$O + ${}^{12}$C using the active-target detector MuSIC@Indiana. Examination of the cross-section just above the barrier reveals a significant suppression of fusion for the ${}^{19}$O + ${}^{12}$C system at E${}_{c.m.}$~12 MeV. This suppression may be due to the formation of a transient ${}^{18}$O-n-${}^{12}$C molecule-like complex favored at a particular angular momentum. Mean-field level models are used as a reference to understand the measured fusion excitation functions.

4 figures; supplementary file