3 research outputs found
No-core shell model for 48-Ca, 48-Sc and 48-Ti
We report the first no-core shell model results for , and
with derived and modified two-body Hamiltonians. We use an oscillator
basis with a limited range around and a limited model space up to . No single-particle
energies are used. We find that the charge dependence of the bulk binding
energy of eight A=48 nuclei is reasonably described with an effective
Hamiltonian derived from the CD-Bonn interaction while there is an overall
underbinding by about 0.4 MeV/nucleon. However, the resulting spectra exhibit
deficiencies that are anticipated due to: (1) basis space limitations and/or
the absence of effective many-body interactions; and, (2) the absence of
genuine three-nucleon interactions. We then introduce additive
isospin-dependent central terms plus a tensor force to our Hamiltonian and
achieve accurate binding energies and reasonable spectra for all three nuclei.
The resulting no-core shell model opens a path for applications to the
double-beta () decay process.Comment: Revised content and added reference
The beta-beta two neutrino decay in 48Ca
A schematic study of the -decay of is made in a
shell-model approach. The emphasis is especially put on the role of the
spin-orbit potential in relation with the contribution of other terms in the
strong interaction. This is discussed with a particular attention to the
behavior of these ones under the SU(4) symmetry. Different methods in
calculating the transition amplitude are also looked at with the aim to
determine their reliability and, eventually, why they don't work. Further
aspects relative to the failure of the Operator Expansion Method to reproduce
the results of more elaborate calculations are examined.Comment: 24 pages, 5 figure