Shell-model calculations on Ni and Cu isotopes

Abstract

Binding energies, excitation energies and spectroscopic factors have been calculated for 57-67Ni and 58-68Cu in an unrestricted (2p3/2, lJ;~2,2p1,2 ) shell-model space. The effective two-body matrix elements are obtained from the modified surface delta interaction (MSDI) and from a least-squares fit to experimental binding and excitation energies (ASDI). The average deviation between about 100 experimental and calculated energies is 0.14 MeV for MSDI and 0.08 MeV for ASDI. Excitation energies of high-spin states are given also. Spectroscopic factors have been calculated for all single-nucleon transfer reactions on stable Ni or Cu targets leading to Ni or Cu isotopes. For spectroscopic factors larger than 0.4 the average deviation between theory and experiment is about 30 %. The experimentally observed and calculated spectroscopic strengths are compared by using sum rules and are found to be consistent. An extensive compilation has been made of experimental data on energies, J~ assignments and spectroscopic factors.

Gamow-Teller strength inFe54andFe

“…[8], obtaining S + = 9.12. A similar calculation by Aufderheide et al [9] yields S + = 9.31 (interaction from [10,11]). Muto [12], using the interaction [13], made a t =2-like calculation that did not respect the 3(N − Z) sum rule, but the author estimated the influence of this violation and proposed S + =7.4.…”

“…Bloom and Fuller made a t = 0 calculation [7] that yields S + = 10.0 (interaction from [8]). Anantaraman et al [22] (interaction from [10,11]) obtain S + = 9.25 for t = 0 and S + = 7.38 for t = 1. The SMMC result [23] is shown in table I together with the numbers coming out of several truncations for both KB3 and BR interactions.…”

Beta-Decay Studies in N ≈ Z Nuclei Using No-Core Configuration-Interaction Model

“…First two columns show old and new experimental data, see [6] for details. Next three columns collect the results of shell-model calculations using MSDI3 [13], GXPF1 [14], and GXPF1A [15] interactions, respectively. Last column shows the results obtained in this work using six reference Slater determinants described in the text.…”

Calculated corrections to superallowed Fermiβdecay: New evaluation of the nuclear-structure-dependent terms

“…This model space is the one used by Koops and Glaudemans [36] in their study of nickel and copper isotopes. We found this model space, with a modified surface delta interaction (MSDI) as used in [36], gave acceptable spectra for the beta-decaying nuclei, with excited 0 + states at about the right excitation energy.…”