34948294
Heavy baryons as Skyrmions with 1/mQ corrections.
We take into account the 1/[ital m][sub [ital Q]] corrections up to 1/[ital N][sub [ital c]] order in the heavy-meson-soliton bound state approach for heavy baryons. With these corrections, the mass spectra of baryons with [ital c] quarks as well as of those with [ital b] quarks are well reproduced. For charmed baryons, however, the correction to the mass spectra amounts to about 300 MeV, which is not small compared to the leading order binding energy, [similar to]800 MeV.
119359306
Neutral pion decay in dense Skyrmion matter
We study the density dependence of the decay {pi}{sup 0}{yields}{gamma}{gamma} using the Skyrme Lagrangian to describe simultaneously both the matter background and mesonic fluctuations. The classical ground state configuration has different chiral properties depending on the Skyrmion density, which is reflected in the physical properties of pion fluctuating on top of the classical background. This leads to large suppression at high density of both photo-production from the neutral pion and the reverse process. The effective charges of {pi}{sup {+-}} are also discussed in the same framework.
119028598
Half-Skyrmions, Tensor Forces and Symmetry Energy in Cold Dense Matter
In a previous article, the 4D half-skyrmion (or 5D dyonic salt) structure of dense baryonic matter described in crystalline configuration in the large Nc limit was shown to have nontrivial consequences on how anti-kaons behave in compressed nuclear matter with a possible implication on an “ice-9” phenomenon of deeply bound kaonic matter and condensed kaons in compact stars. We extend the analysis to make a further prediction on the scaling properties of hadrons that have a surprising effect on the nuclear tensor forces, the symmetry energy and hence on the phase structure at high density. We treat this problem relying on certain topological structure of chiral solitons. Combined with what can be deduced from hidden local symmetry for hadrons in dense medium and the “soft” dilatonic degree of freedom associated with the trace anomaly of QCD, we uncover a novel structure of chiral symmetry in the “supersoft” symmetry energy that can influence the structure of neutron stars. .
18951551
Dense QCD: Overhauser or BCS pairing?
We discuss the Overhauser effect (particle-hole pairing) versus the BCS effect (particle-particle or hole-hole pairing) in QCD at large quark density. In weak coupling and to leading logarithm accuracy, the pairing energies can be estimated exactly. For a small number of colors, the BCS effect overtakes the Overhauser effect, while for a large number of colors the opposite takes place, in agreement with a recent renormalization group argument. In strong coupling with large pairing energies, the Overhauser effect may be dominant for any number of colors, suggesting that QCD may crystallize into an insulator at a few times nuclear matter density, a situation reminiscent of dense Skyrmions. The Overhauser effect is dominant in QCD in 1+1 dimensions, although susceptible to quantum effects. It is sensitive to temperature in all dimensions. (c) 2000 The American Physical Society.
14302817
Vector mesons and dense skyrmion matter
Abstract In our continuing effort to understand hadronic matter at high density, we have developed a unified field theoretic formalism for dense skyrmion matter using a single Lagrangian to describe simultaneously both matter and meson fluctuations and studied in-medium properties of hadrons. Dropping the quartic Skyrme term, we incorporate into our previous Lagrangian the vector mesons ρ and ω in a form which is consistent with the symmetries of QCD. The results that we have obtained, reported here, expose a hitherto unsuspected puzzle associated with the role the ω meson plays at short distance. Since the ω meson couples to baryon density, it leads to a pseudo-gap scenario for the chiral symmetry phase transition, which is at variance with standard scenario of QCD at the phase transition. We find that in the presence of the ω mesons, the scale-anomaly dilaton field is prevented from developing a vanishing vacuum expectation value at the chiral restoration, as a consequence of which the in-medium pion decay constant does not vanish. This seems to indicate that the ω degree of freedom obstructs the “vector manifestation” which is considered to be a generic feature of effective field theories matched to QCD.
116131889
Chiral Model Predictions for Strange Form Factors
7089219
Energy dependence of the Gamow-Teller strength in p-shell nuclei observed in the (n,p) reaction.
Cross sections from 0{degree} to 10{degree} (lab) have been measured for ground-state Gamow-Teller transitions for the reactions {sup 6}Li({ital n},{ital p}){sup 6}He, {sup 12}C({ital n},{ital p}){sup 12}B and {sup 13}C({ital n},{ital p}){sup 13}B from 60 to 260 MeV. The 90-m station at the Weapons Neutron Research facility at Los Alamos National Laboratory was used to obtain these data. Unit cross sections ({sigma}) have been obtained and are compared with existing ({ital n},{ital p}) and ({ital p},{ital n}) data. The volume integrals ({ital J}{sub {sigma}{tau}}) for the spin-flip isospin-flip part of the effective nucleon-nucleon interaction have also been obtained and are compared with theoretical predictions.