English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Open

Background: Computationally tractable models of atomic nuclei is a long-timegoal of nuclear structure physics. A flexible framework which easily includesexcited states and many-body correlations is the configuration-interactionshell model (SM), but the exponential growth of the basis means one needs anefficient truncation scheme, ideally one that includes both deformation andpairing correlations.  Purpose: We propose an efficient truncation scheme of the SM: starting from apair condensate variationally defined by Hartree-Fock single-particle statesand the particle-number conserved Bardeen-Cooper-Schrieffer (NBCS)approximation, we carry out projection of states with good angular momentum.  Methods: After generating Hartree-Fock single-particle states with Kramersdegeneracy in a SM space, we optimize the pair amplitudes in the NBCS byminimizing the energy, and then use linear algebra projection (LAP) of stateswith good angular momentum. Both NBCS and LAP are computationally fast.  Results: Our calculations yield good agreement with fullconfiguration-interaction SM calculations for low-lying states of transitionaland rotational nuclei with axially symmetric and triaxial deformation inmedium- and heavy-mass regions: $^{44,46,48}$Ti, $^{48,50}$Cr, $^{52}$Fe,$^{60,62,64}$Zn, $^{66,68}$Ge, $^{68}$Se, and $^{108,110}$Xe. We predictlow-lying states of $^{112-114}\textrm{Ba}$ and $^{116-120}\textrm{Ce}$, nucleidifficult to reach by large-scale SM calculations.  Conclusions: Both pair correlation and the configuration mixing betweendifferent intrinsic states play a key role in reproducing collectivity andshape coexistence, demonstrating the utility of this truncation scheme of theSM to study transitional and deformed nuclei.

Nucleon-pair truncation of the shell model for medium-heavy nuclei