QRPA and its extensions in a solvable model
Abstract
An exactly solvable model is introduced, which is equivalent to the exact shell-model treatment of protons and neutrons in a single j-shell for Fermi-type excitations. Exact energies, quasiparticle numbers and double beta decay Fermi amplitudes are computed and compared with the results of both the standard quasiparticle random phase approximation (QRPA) and the renormalized one (RQRPA), and also with those corresponding to the hamiltonian in the quasiparticle basis (qp). A zero excitation energy state is found in the exact case, occuring at a value of the residual particle-particle interaction at which the QRPA collapse. The RQRPA and the qp solutions do not include this zero-energy eigenvalue in their spectra, probably due to spurious correlations.
Cite
@article{arxiv.nucl-th/9701055,
title = {QRPA and its extensions in a solvable model},
author = {Jorge G. Hirsch and Peter O. Hess and Osvaldo Civitarese},
journal= {arXiv preprint arXiv:nucl-th/9701055},
year = {2007}
}
Comments
13 pages, plus 5 figures included in the Latex file. Proc. XX Symposium on Nuclear Physics, Oaxtepec, Mexico, 6-9 Jan 1997. Submitted to Revista Mexicana de Fisica