29,107 research outputs found
Chiral approach to antikaon s- and p-wave interactions in dense nuclear matter
The properties of the antikaons in nuclear matter are investigated from a
chiral unitary approach which incorporates the s- and p-waves of the interaction. To obtain the in-medium meson-baryon amplitudes we include,
in a self-consistent way, Pauli blocking effects, meson self-energies corrected
by nuclear short-range correlations and baryon binding potentials. We pay
special attention to investigating the validity of the on-shell factorization,
showing that it cannot be applied in the evaluation of the in-medium
corrections to the p-wave amplitudes. In nuclear matter at saturation energy,
the and develop an attractive potential of about -30 MeV,
while the pole remains at the free space value although its width
gets sensibly increased to about 80 MeV. The antikaon also develops a moderate
attraction that does not support the existence of very deep and narrow bound
states, confirming the findings of previous self-consistent calculations.Comment: 29 pages, 12 figures, published in Physical Review
Charm at FAIR
Charmed mesons in hot and dense matter are studied within a self-consistent
coupled-channel approach for the experimental conditions of density and
temperature expected at the CBM experiment at FAIR/GSI. The meson spectral
function broadens with increasing density with an extended tail towards lower
energies due to and
excitations. The in-medium meson mass increases with density. We also
discuss the consequences for the renormalized properties in nuclear matter of
the charm scalar and D(2400), and the predicted hidden charm
X(3700) resonances at FAIR energies.Comment: 6 pages, 3 figures, to appear in the proceedings of ExcitedQCD 09,
Zakopane, Poland, 8-14 February 200
Strange and charm mesons at FAIR
We study the properties of strange and charm mesons in hot and dense matter
within a self-consistent coupled-channel approach for the experimental
conditions of density and temperature expected for the CBM experiment at
FAIR/GSI. The in-medium solution at finite temperature accounts for Pauli
blocking effects, mean-field binding of all the baryons involved, and meson
self-energies. We analyze the behaviour in this hot and dense environment of
dynamically-generated baryonic resonances together with the evolution with
density and temperature of the strange and open-charm meson spectral functions.
We test the spectral functions for strange mesons using energy-weighted sum
rules and finally discuss the implications of the properties of charm mesons on
the D_{s0}(2317) and the predicted X(3700) scalar resonances.Comment: 12 pages, 9 figures, invited talk at XXXI Mazurian Lakes Conference
on Physics: Nuclear Physics and the Road to FAIR, August 30-September 6,
2009, Piaski, Polan
The platinum nuclei: concealed configuration mixing and shape coexistence
The role of configuration mixing in the Pt region is investigated. For this
chain of isotopes, the nature of the ground state changes smoothly, being
spherical around mass and and deformed around the
mid-shell N=104 region. This has a dramatic effect on the systematics of the
energy spectra as compared to the systematics in the Pb and Hg nuclei.
Interacting Boson Model with configuration mixing calculations are presented
for gyromagnetic factors, -decay hindrance factors, and isotope shifts.
The necessity of incorporating intruder configurations to obtain an accurate
description of the latter properties becomes evident.Comment: Accepted in Physical Review
Energy weighted sum rules for mesons in hot and dense matter
We study energy weighted sum rules of the pion and kaon propagator in nuclear
matter at finite temperature. The sum rules are obtained from matching the
Dyson form of the meson propagator with its spectral Lehmann representation at
low and high energies. We calculate the sum rules for specific models of the
kaon and pion self-energy. The in-medium spectral densities of the K and anti-K
mesons are obtained from a chiral unitary approach in coupled channels which
incorporates the S- and P-waves of the kaon-nucleon interaction. The pion
self-energy is determined from the P-wave coupling to particle-hole and
Delta-hole excitations, modified by short range correlations. The sum rules for
the lower energy weights are fulfilled satisfactorily and reflect the
contributions from the different quasi-particle and collective modes of the
meson spectral function. We discuss the sensitivity of the sum rules to the
distribution of spectral strength and their usefulness as quality tests of
model calculations.Comment: 19 pages, 6 figures; one figure added, enhanced discussion, version
to appear in PR
Charmed hadrons in nuclear medium
We study the properties of charmed hadrons in dense matter within a
coupled-channel approach which accounts for Pauli blocking effects and meson
self-energies in a self-consistent manner. We analyze the behaviour in this
dense environment of dynamically-generated baryonic resonances as well as the
open-charm meson spectral functions. We discuss the implications of the
in-medium properties of open-charm mesons on the and the
predicted X(3700) scalar resonances.Comment: 4 pages, 5 figures, invited parallel talk in the 5th International
Conference on Quarks and Nuclear Physics (QNP09), Beijing, September 21-26,
200
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