3 research outputs found
Beta-decay in odd-A and even-even proton-rich Kr isotopes
Beta-decay properties of proton-rich odd-A and even-even Krypton isotopes are
studied in the framework of a deformed selfconsistent Hartree-Fock calculation
with density-dependent Skyrme forces, including pairing correlations between
like nucleons in BCS approximation. Residual spin-isospin interactions are
consistently included in the particle-hole and particle-particle channels and
treated in Quasiparticle Random Phase Approximation. The similarities and
differences in the treatment of even-even and odd-A nuclei are stressed.
Comparison to available experimental information is done for Gamow-Teller
strength distributions, summed strengths, and half-lives. The dependence of
these observables on deformation is particularly emphasized in a search for
signatures of the shape of the parent nucleus.Comment: 29 pages, 16 figure
Tests of the random phase approximation for transition strengths
We investigate the reliability of transition strengths computed in the
random-phase approximation (RPA), comparing with exact results from
diagonalization in full shell-model spaces. The RPA and
shell-model results are in reasonable agreement for most transitions; however
some very low-lying collective transitions, such as isoscalar quadrupole, are
in serious disagreement. We suggest the failure lies with incomplete
restoration of broken symmetries in the RPA. Furthermore we prove, analytically
and numerically, that standard statements regarding the energy-weighted sum
rule in the RPA do not hold if an exact symmetry is broken.Comment: 11 pages, 7 figures; Appendix added with new proof regarding
violation of energy-weighted sum rul