The two-particle, one-hole shell model with a harmonic oscillator basis is employed for a calculation of isospin-split giant resonance states in ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$ and ${}_{}{}^{17}{}_{}{}^{}\mathrm{O}$ that can be reached from the ground state by $\Delta T=0,1\mathrm{}$ transitions of type $E1$ or $M2\mathrm{}$. Residual forces used were a zero-range Soper mixture as well as the separable Tabakin potential. We calculate photoabsorption strengths which for ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$ agree with the available data and with a previous calculation of Easlea using the Soper force; for the Tabakin force, this agreement is achieved without Easlea's ad hoc modification of the interaction. We also evaluate the inelastic form factors for electroexcitation of the ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$ resonance levels, thereby identifying isospin and spin-isospin collective states.

NUCLEAR REACTIONS ${}_{}{}^{13}{}_{}{}^{}\mathrm{C}$ calculated photonuclear cross sections, electron scattering form factors of giant and pygmy resonances ($T_{>},T_{<}$); ${}_{}{}^{17}{}_{}{}^{}\mathrm{O}$ calculated photonuclear cross sections. Used two-particle, one-hole shell model.

• Received 31 January 1977

DOI:https://doi.org/10.1103/PhysRevC.16.503