Number conserving particle-hole RPA for superfluid nuclei

TheAuthor(s) - .Published by Elsevier B.V. "This is an open access article under the CCBY license (http://creativecommons.org/licenses/by/4.0/).Funded by SCOAP"We present a number conserving particle-hole RPA theory for collective excitations in the transition from normal to superfluid nuclei. The method derives from an RPA theory developed long ago in quantum chemistry using antisymmetric geminal powers, or equivalently number projected HFB states, as reference states. We show within a minimal model of pairing plus monopole interactions that the number conserving particle-hole RPA excitations evolve smoothly across the superfluid phase transition close to the exact results, contrary to particle-hole RPA in the normal phase and quasiparticle RPA in the superfluid phase that require a change of basis at the broken symmetry point. The new formalism can be applied in a straightforward manner to study particle-hole excitations on top of a number projected HFB state.Consejería de Economía, Conocimiento, Empresas y Universidad de la Junta de Andalucía (Spain) FQM-160 and FQM-370Fondo Europeo de Desarrollo Regional (ERDF), ref. SOMM17/6105/UGRMinisterio de Ciencia, Innovación y Universidades and the ERDF under Projects No. FIS2015-63770-P, FIS2017-88410-P and PGC2018-094180-B-I00CEAFMC and Universidad de Huelva High Performance Computer (HPC@UHU) funded by FEDER/MINECO project UNHU-15CE-284

Number conserving particle-hole RPA for superfluid nuclei

We present a number conserving particle-hole RPA theory for collective excitations in the transition from normal to superfluid nuclei. The method derives from an RPA theory developed long ago in quantum chemistry using antisymmetric geminal powers, or equivalently number projected HFB states, as reference states. We show within a minimal model of pairing plus monopole interactions that the number conserving particle-hole RPA excitations evolve smoothly across the superfluid phase transition close to the exact results, contrary to particle-hole RPA in the normal phase and quasiparticle RPA in the superfluid phase that require a change of basis at the broken symmetry point. The new formalism can be applied in a straightforward manner to study particle-hole excitations on top of a number projected HFB state.This work has been partially supported by the Consejeria de Economia, Conocimiento, Empresas y Universidad de la Junta de Andalucia(Spain) under Groups FQM-160 and FQM-370 and by European Regional Development Fund (ERDF), ref. SOMM17/6105/UGR. We acknowledge financial support from the Spanish Ministerio de Ciencia, Innovacion y Universidades and the ERDF under Projects No. FIS2015-63770-P, FIS2017-88410-P and PGC2018-094180-B-I00. Resources supporting this work were provided by the CEAFMC and Universidad de Huelva High Performance Computer (HPC@UHU) funded by FEDER/MINECO project UNHU-15CE-2848

Number conserving particle-hole RPA for superfluid nuclei

5 pags., 3 figs.-- Open Access funded by Creative Commons Atribution Licence 4.0We present a number conserving particle-hole RPA theory for collective excitations in the transition from normal to superfluid nuclei. The method derives from an RPA theory developed long ago in quantum chemistry using antisymmetric geminal powers, or equivalently number projected HFB states, as reference states. We show within a minimal model of pairing plus monopole interactions that the number conserving particle-hole RPA excitations evolve smoothly across the superfluid phase transition close to the exact results, contrary to particle-hole RPA in the normal phase and quasiparticle RPA in the superfluid phase that require a change of basis at the broken symmetry point. The new formalism can be applied in a straightforward manner to study particle-hole excitations on top of a number projected HFB state.This work has been partially supported by the Consejería de Economía, Conocimiento, Empresas y Universidad de la Junta de Andalucía (Spain) under Groups FQM-160 and FQM-370 and by European Regional Development Fund (ERDF), ref. SOMM17/6105/UGR. We acknowledge financial support from the Spanish Ministerio de Ciencia, Innovación y Universidades and the ERDF under Projects No. FIS2015-63770-P, FIS2017-88410-P and PGC2018-094180-B-I00. Resources supporting this work were provided by the CEAFMC and Universidad de Huelva High Performance Computer (HPC@UHU) funded by FEDER/MINECO project UNHU-15CE-2848