Continuum—Shell-Model Description of Compound Resonances in the SystemO16+n

Bound and continuum properties of the system ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}+n$ are obtained from a microscopic model by means of an extended $R$-matrix formalism. The model includes configurations arising from excitation of up to four particles from the closed ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ core and provides a useful dynamical description of the observed low-energy spectrum.