8,776 research outputs found
Superheavy element production, nucleus-nucleus potential and mu-catalysis
The semi-microscopic potential between heavy nuclei is evaluated for various
colliding ions in the approach of frozen densities in the framework of the
extended Thomas-Fermi approximation with hbar^2 correction terms in the kinetic
energy density functional. The proton and neutron densities of each nucleus are
obtained in the Hartree-Fock-BCS approximation with SkM* parameter set of the
Skyrme force. A simple expression for the nuclear interaction potential between
spherical nuclei is presented. It is shown that muon bound with light
projectile induces the superheavy elements production in nucleus-nucleus
collisions.Comment: 9 pages, 4 figures, RevTex, Tours 5 Symposium on Nuclear Physics,
Tours, August 200
Nuclear reactions in hot stellar matter and nuclear surface deformation
Cross-sections for capture reactions of charged particles in hot stellar
matter turn out be increased by the quadrupole surface oscillations, if the
corresponding phonon energies are of the order of the star temperature. The
increase is studied in a model that combines barrier distribution induced by
surface oscillations and tunneling. The capture of charged particles by nuclei
with well-deformed ground-state is enhanced in stellar matter. It is found that
the influence of quadrupole surface deformation on the nuclear reactions in
stars grows, when mass and proton numbers in colliding nuclei increase.Comment: 12 pages, 10 figure
Space-time velocity correlation function for random walks
Space-time correlation functions constitute a useful instrument from the
research toolkit of continuous-media and many-body physics. We adopt here this
concept for single-particle random walks and demonstrate that the corresponding
space-time velocity auto-correlation functions reveal correlations which extend
in time much longer than estimated with the commonly employed temporal
correlation functions. A generic feature of considered random-walk processes is
an effect of velocity echo identified by the existence of time-dependent
regions where most of the walkers are moving in the direction opposite to their
initial motion. We discuss the relevance of the space-time velocity correlation
functions for the experimental studies of cold atom dynamics in an optical
potential and charge transport on micro- and nano-scales.Comment: Phys. Rev. Lett., in pres
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