1,395 research outputs found
Screening Effects in Superfluid Nuclear and Neutron Matter within Brueckner Theory
Effects of medium polarization are studied for pairing in neutron and
nuclear matter. The screening potential is calculated in the RPA limit,
suitably renormalized to cure the low density mechanical instability of nuclear
matter. The selfenergy corrections are consistently included resulting in a
strong depletion of the Fermi surface. All medium effects are calculated based
on the Brueckner theory. The gap is determined from the generalized gap
equation. The selfenergy corrections always lead to a quenching of the gap,
which is enhanced by the screening effect of the pairing potential in neutron
matter, whereas it is almost completely compensated by the antiscreening effect
in nuclear matter.Comment: 8 pages, 6 Postscript figure
Time-dependent Internal DFT formalism and Kohn-Sham scheme
We generalize to the time-dependent case the stationary Internal DFT /
Kohn-Sham formalism presented in Ref. [14]. We prove that, in the
time-dependent case, the internal properties of a self-bound system (as an
atomic nuclei) are all defined by the internal one-body density and the initial
state. We set-up a time-dependent Internal Kohn-Sham scheme as a practical way
to compute the internal density. The main difference with the traditional DFT /
Kohn-Sham formalism is the inclusion of the center-of-mass correlations in the
functional.Comment: 13 pages. To be published in Phys. Rev.
BCS-BEC crossover of neutron pairs in symmetric and asymmetric nuclear matter
We propose new types of density dependent contact pairing interaction which
reproduce the pairing gaps in symmetric and neutron matter obtained by a
microscopic treatment based on the nucleon-nucleon interaction. These
interactions are able to simulate the pairing gaps of either the bare
interaction or the interaction screened by the medium polarization effects. It
is shown that the medium polarization effects cannot be cast into the density
power law function usually introduced together with the contact interaction and
require the introduction of another isoscalar term. The BCS-BEC crossover of
neutrons pairs in symmetric and symmetric nuclear matter is studied by using
these contact interactions. It is shown that the bare and screened pairing
interactions lead to different features of the BCS-BEC crossover in symmetric
nuclear matter. For the screened pairing interaction, a two-neutron BEC state
is formed in symmetric matter at fm (neutron density
). Contrary the bare interaction does not form the
BEC state at any neutron density
Screening of nuclear pairing in nuclear and neutron matter
The screening potential in the and pairing channels in
neutron and nuclear matter in different approximations is discussed. It is
found that the vertex corrections to the potential are much stronger in nuclear
matter than in neutron matter.Comment: 11 pages, 8 figures, revtex4 styl
Time-odd mean fields in the rotating frame: microscopic nature of nuclear magnetism
The microscopic role of nuclear magnetism in rotating frame is investigated
for the first time in the framework of the cranked relativistic mean field
theory. It is shown that nuclear magnetism modifies the expectation values of
single-particle spin, orbital and total angular momenta along the rotational
axis effectively creating additional angular momentum. This effect leads to the
increase of kinematic and dynamic moments of inertia at given rotational
frequency and has an impact on effective alignments.Comment: 16 pages, 4 figures, submitted to Physical Review
Fluctuation and dissipation dynamics in fusion reactions from stochastic mean-field approach
By projecting the stochastic mean-field dynamics on a suitable collective
path during the entrance channel of heavy-ion collisions, expressions for
transport coefficients associated with relative distance are extracted. These
transport coefficients, which have similar forms to those familiar from nucleon
exchange model, are evaluated by carrying out TDHF simulations. The
calculations provide an accurate description of the magnitude and form factor
of transport coefficients associated with one-body dissipation and fluctuation
mechanism.Comment: 9 pages, 5 figure
Breathing mode in an improved transport approach
The nuclear breathing-mode giant monopole resonance is studied within an
improved relativistic Boltzmann-Uehling-Uhlenbeck (BUU) transport approach. As
a new feature, the numerical treatment of ground state nuclei and their
phase-space evolution is realized with the same semiclassical energy density
functional. With this new method a very good stability of ground state nuclei
in BUU simulations is achieved. This is important in extracting clear
breathing-mode signals for the excitation energy and, in particular, for the
lifetime from transport theoretical studies including mean-field and
collisional effects.Comment: 33 pages, 11 figures, accepted for publication in Phys. Rev.
Plantar Erythrodysesthesia Caused by Antiretroviral Treatment: A Case Report and Review of the Literature
Palmoplantar erythrodysesthesia is an uncommon localised cutaneous reaction to certain chemotherapeutic agents and characterized by painful palmoplantar erythema and dysesthesia. To the best of our knowledge, we report the first case of plantar erythrodysesthesia in a 40-year-old male patient receiving an antiretroviral combination therapy for HIV
Superheavy nuclei in relativistic effective Lagrangian model
Isotopic and isotonic chains of superheavy nuclei are analyzed to search for
spherical double shell closures beyond Z=82 and N=126 within the new effective
field theory model of Furnstahl, Serot, and Tang for the relativistic nuclear
many-body problem. We take into account several indicators to identify the
occurrence of possible shell closures, such as two-nucleon separation energies,
two-nucleon shell gaps, average pairing gaps, and the shell correction energy.
The effective Lagrangian model predicts N=172 and Z=120 and N=258 and Z=120 as
spherical doubly magic superheavy nuclei, whereas N=184 and Z=114 show some
magic character depending on the parameter set. The magicity of a particular
neutron (proton) number in the analyzed mass region is found to depend on the
number of protons (neutrons) present in the nucleus.Comment: 26 pages, REVTeX, 10 ps figures; changed conten
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