142 research outputs found
Low momentum nucleon-nucleon potential and shell model effective interactions
A low momentum nucleon-nucleon (NN) potential V-low-k is derived from meson
exhange potentials by integrating out the model dependent high momentum modes
of V_NN. The smooth and approximately unique V-low-k is used as input for shell
model calculations instead of the usual Brueckner G matrix. Such an approach
eliminates the nuclear mass dependence of the input interaction one finds in
the G matrix approach, allowing the same input interaction to be used in
different nuclear regions. Shell model calculations of 18O, 134Te and 135I
using the same input V-low-k have been performed. For cut-off momentum Lambda
in the vicinity of 2 fm-1, our calculated low-lying spectra for these nuclei
are in good agreement with experiments, and are weakly dependent on Lambda.Comment: 5 pages, 5 figure
Hidden spin-isospin exchange symmetry
The strong interactions among nucleons have an approximate spin-isospin
exchange symmetry that arises from the properties of quantum chromodynamics in
the limit of many colors, . However this large- symmetry is well
hidden and reveals itself only when averaging over intrinsic spin orientations.
Furthermore, the symmetry is obscured unless the momentum resolution scale is
close to an optimal scale that we call . We show
that the large- derivation requires a momentum resolution scale of
MeV. We derive a set of spin-isospin
exchange sum rules and discuss implications for the spectrum of P and
applications to nuclear forces, nuclear structure calculations, and
three-nucleon interactions.Comment: 5 pages (main) + 3 pages (supplemental materials), 1 figure (main) +
4 figures (supplemental materials), final version to appear in Phys. Rev.
Let
Realistic shell-model calculations for proton particle-neutron hole nuclei around 132Sn
We have performed shell-model calculations for nuclei with proton particles
and neutron holes around 132Sn using a realistic effective interaction derived
from the CD-Bonn nucleon-nucleon potential. For the proton-neutron channel this
is explicitly done in the particle-hole formalism. The calculated results are
compared with the available experimental data, particular attention being
focused on the proton particle-neutron hole multiplets. A very good agreement
is obtained for all the four nuclei considered, 132Sb, 130Sb, 133Te and 131Sb.
We predict many low-energy states which have no experimental counterpart. This
may stimulate, and be helpful to, future experiments.Comment: 8 pages, 6 figures, to be published on Physical Review
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