Shape coexistence effects in⁷⁸Kr

Abstract

Results are presented on shape coexistence effects in the nucleus 78 Kr obtained within the complex version of the EXCITED VAMPIR variational approach. Oblate-prolate coexistence and mixing is found to be responsible for the characteristic features identified at low excitation energy for low and intermediate as well as high spins. At the highest investigated spins, the high density of configurations having different deformations results in the fragmentation of B(E2) strengths explaining the experimentally identified forking of the spectrum. The present investigation indicates the essential role played by particular neutron-proton matrix elements of the effective interaction on the oblate-prolate coexistence and mixing in the 78 Kr nucleus.

Shape evolution and Gamow-Tellerβ-decay of neutron-rich A∼100 nuclei within beyond-mean-field approach

“…The precise and reliable description of the lowest states of the parent nucleus and of the states in the β window in the daughter nucleus necessary for a good description of the Gamow-Teller β-decay properties is a more difficult task for nuclei dominated by shape coexistence and mixing. Our recent self-consistent investigation 01012-p.2 72% 67% 32% 77% 20% 38% 61% 89% 9% 89% 8% 16% 82% 3% 96% 82% 16% 45% 53% 38% 61% 63% 37% 61% 38% 68% 30% 79% 19% of the Gamow-Teller strength distributions, β-decay halflives, and β-delayed neutron emission probabilities for 104 Zr and 106 Zr nuclei within the complex Excited Vampir model [13] indicated good agreement with the experimental data [14] . Recently have been published the first results of the total absorption gamma spectrometer (TAGS) measurements of nuclei that are important contributors to the decay heat in nuclear reactors and the self-consistent description of their Gamow-Teller β decay properties [15].…”

Overview of neutron–proton pairing

“…Petrovici et al [179] calculated the GT strength for the β + decay of the astrophysical relevant nuclides Fig. 50) was found.…”

Isospin-symmetry breaking and shape coexistence inA≈70analogs

“…I start with an isospin symmetric basis and then introduce the Coulomb shifts for the proton single particle levels resulting from the 40Ca core by performing spherically symmetric Hartree-Fock calculations using the Gogny interaction D1S in a 21 major-shell basis [23],…”

“…Investigations based on the variational approaches o f the VAMPIR model fam ily have been successfully perform ed for the description o f a variety o f nuclear structure phenom ena in the A 70 mass region, not only in nuclei along the valley o f fi stability, but also in som e exotic nuclei close to the proton drip line [20][21][22][23][24], T he com plex excited VAM PIR approach allows for a unified description o f low-and high-spin states including in the projected m ean field neutron-proton correlations in both the T = 1 and T = 0 channels and general tw o-nucleon unnatural-parity correlations. The oblate-prolate coexistence and mixing, and the variation o f the deform ation w ith mass number, increasing spin, as well as excitation energy, have been com pared with the available experim ental inform ation.…”