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Systematic study of deformed nuclei at the drip lines and beyond
An improved prescription for choosing a transformed harmonic oscillator (THO)
basis for use in configuration-space Hartree-Fock-Bogoliubov (HFB) calculations
is presented. The new HFB+THO framework that follows accurately reproduces the
results of coordinate-space HFB calculations for spherical nuclei, including
those that are weakly bound. Furthermore, it is fully automated, facilitating
its use in systematic investigations of large sets of nuclei throughout the
periodic table. As a first application, we have carried out calculations using
the Skyrme Force SLy4 and volume pairing, with exact particle number projection
following application of the Lipkin-Nogami prescription. Calculations were
performed for all even-even nuclei from the proton drip line to the neutron
drip line having proton numbers Z=2,4,...,108 and neutron numbers
N=2,4,...,188. We focus on nuclei near the neutron drip line and find that
there exist numerous particle-bound even-even nuclei (i.e., nuclei with
negative Fermi energies) that have at the same time negative two-neutron
separation energies. This phenomenon, which was earlier noted for light nuclei,
is attributed to bound shape isomers beyond the drip line.Comment: 12 ReVTeX4 pages, 6 EPS figures. See also
http://www.fuw.edu.pl/~dobaczew/thodri/thodri.htm
Computational models of visual neurons specialised in the detection of periodic and aperiodic oriented visual stimuli:Bar and grating cells
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