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DOE OSTI · 21499575

Self-consistent continuum random-phase approximation calculations with finite-range interactions

De Donno, V·Co', G·Anguiano, M·Lallena, A M
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Abstract

We present a technique that treats, without approximations, the continuum part of the excitation spectrum in random phase approximation calculations with finite-range interactions. The interaction used in Hartree-Fock calculations to generate the single-particle basis is also used in continuum random phase approximation calculations. We show results for electric dipole and quadrupole excitations in {sup 16}O, {sup 22}O, {sup 24}O, {sup 40}Ca, {sup 48}Ca, and {sup 52}Ca nuclei. We compare our results with those of the traditional discrete random phase approximation, with continuum independent-particle model results, and with results obtained by a phenomenological random phase approximation approach. We study the relevance of the continuum, of the residual interaction, and of the self-consistency. We also compare our results with the available total photoabsorption cross-section data.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSALKALINE EARTH ISOTOPESAPPROXIMATIONSBETA DECAY RADIOISOTOPESBETA-MINUS DECAY RADIOISOTOPESCALCIUM 40CALCIUM 48CALCIUM 52CALCIUM ISOTOPESCALCULATION METHODSCOMPARATIVE EVALUATIONSCOMPUTERIZED SIMULATIONCROSS SECTIONSDIPOLESELECTRIC DIPOLESENERGY-LEVEL TRANSITIONSEVALUATIONEVEN-EVEN NUCLEIEXCITATIONFINITE-RANGE INTERACTIONSHARTREE-FOCK METHODINTERACTIONSINTERMEDIATE MASS NUCLEIISOTOPESLIGHT NUCLEIMATHEMATICAL MODELSMILLISECONDS LIVING RADIOISOTOPESMULTIPOLESNUCLEAR MODELSNUCLEIOXYGEN 16OXYGEN 22OXYGEN 24OXYGEN ISOTOPESQUADRUPOLESRADIOISOTOPESRANDOM PHASE APPROXIMATIONRESIDUAL INTERACTIONSSECONDS LIVING RADIOISOTOPESSIMULATIONSINGLE-PARTICLE MODELSPECTRASTABLE ISOTOPES

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De Donno, V, Co', G, Anguiano, M, Lallena, A M. 2011-04-15. Self-consistent continuum random-phase approximation calculations with finite-range interactions. https://doi.org/10.1103/physrevc.83.044324

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