121652117
The L-G Phase Transition and the Nucleon–Nucleon Interaction Potential within QHD-I Model
The nucleon–nucleon interaction potential in hot/dense nuclear matter is studied within the QHD-I model. We find that a Yukawa potential, which contains attractive and repulsive terms, acting between nucleons is modified by the variation of the Debye mass. In particular, a nucleon system described by this Yukawa potential will be unbound at some critical T and μ. The critical point is very close to that of the L-G phase transition given in the literatures.
118573990
Three-dimensional correlated-fermion phase separation from analysis of the geometric mean of the individual susceptibilities
A quasi-Gaussian approximation scheme is formulated to study the strongly correlated imbalanced Fermions thermodynamics, where the mean-field theory is not applicable. The non-Gaussian correlation effects are understood to be captured by the statistical geometric mean of the individual susceptibilities. In the three-dimensional unitary fermions ground state, a universal nonlinear scaling transformation relates the physical chemical potentials with the individual Fermi kinetic energies. For the partial polarization phase separation to full polarization, the calculated critical polarization ratio is δC = [1−(1−ξ)6/5]/[1+(1−ξ)6/5] ≐ 0.34. ξ = 4/9 gives the ratio of the symmetric ground state energy density to that of the ideal fermion gas.
122544309
THE MULTI-VALUE OF EFFECTIVE NUCLEON MASS IN HOT/DENSE NUCLEAR MATTER AND THE PHASE TRANSITION
From the Lagrangian of QHD-I model, we investigate the effective nucleon mass under the mean field approximation in a wide temperature region. The multi-solution of self-consistent equation for the effective mass in found. In the high temperature region, the relation between the multi-solutions and the phase transition is analyzed. Furthermore, the variation of energy density in this region is studied.
124840820
Finite-temperature nuclear matter properties within a relativistic σ − ω coupling model
We use the relativistic mean field theory to study the finite temperature nuclear matter properties. The effects of isoscalar $\ensuremath{\sigma}\text{\ensuremath{-}}\ensuremath{\omega}$ coupling on the equation of state and finite temperature properties of symmetric and asymmetric nuclear matter are investigated carefully. For comparison, we also discuss the properties of two nonlinear $\ensuremath{\sigma}$ self-coupling models, namely NL-SH and NL3. It is found that the $\ensuremath{\sigma}\text{\ensuremath{-}}\ensuremath{\omega}$ coupling term can soften the equation of state, but has very limited influence to the critical temperature of the nuclear matter liquid-gas phase transition.
119453402
1S0 pairing correlation in symmetric nuclear matter with Debye screening effects
Abstract The 1 S 0 pairing of symmetric nuclear matter is discussed in the framework of relativistic nuclear theory with Dyson–Schwinger equations (DSEs). The in-medium nucleon and meson propagators are treated in a more self-consistent way through meson polarizations. The screening effects on mesons due to in-medium nucleon excitation are found to reduce the 1 S 0 pairing gap and shift remarkably the gap peak to low density region.
124341359
Thomson Problem approach to relativistic Dirac fermions ground state energy in the unitary limit
53708603
QCD viscosity to entropy density ratio in the hadronic phase
The shear viscosity {eta} of QCD in the hadronic phase is computed by the coupled Boltzmann equations of pions and nucleons in low temperatures and low baryon-number densities. The {eta} to entropy density ratio {eta}/s maps out the nuclear gas-liquid phase transition by forming a valley tracing the phase transition line in the temperature-chemical potential plane. When the phase transition turns into a crossover, the {eta}/s valley gradually disappears. We suspect the general feature for a first-order phase transition is that {eta}/s has a discontinuity in the bottom of the {eta}/s valley. The discontinuity coincides with the phase transition line and ends at the critical point. Beyond the critical point, a smooth {eta}/s valley is seen. However, the valley could disappear further away from the critical point. The {eta}/s measurements might provide an alternative to identify the critical points.
119289986
Minimum Shear Viscosity over Entropy Density at Phase Transition?: A Counterexample
Abstract The ratio η / s , shear viscosity (η) to entropy density (s), reaches its local minimum at the (second order) phase transition temperature in a wide class of systems. It was suspected that this behavior might be universal. However, a counterexample is found in a system of two weakly self-interacting real scalar fields with one of them condensing at low temperatures while the other remains in the symmetric phase. There is no interaction between the two fields. In our mean field analysis the resulting η / s is monotonically decreasing in temperature despite the second order phase transition.
17907752
Observation of hypertritons in Au+Au collisions at \sqrt{s_{NN}} = 200 GeV
We report preliminary results of hypertriton observation in heavy-ion collisions at RHIC. We have identified 157 +- 30 candidates in the current sample containing ~10^8 Au+Au events at \sqrt{s_{NN}} = 200 GeV. The production rate of hypertriton is close to that of helium 3. No extra penalty factor is observed for hypertriton, in contrast to results observed at the AGS.
118906717
Leading chiral corrections to the nucleon generalized parton distributions
Using heavy baryon chiral perturbation theory we study the leading chiral corrections to the complete set of nucleon generalized parton distributions (GPDs). We compute the leading quark mass and momentum transfer dependence of the moments of nucleon GPDs through the nucleon off-forward twist-2 matrix elements. These results are then applied to get insight on the GPDs and their impact parameter space distributions.
15921154
Connecting the quenched and unquenched worlds via the large Nc world
Abstract In the large N c (number of colors) limit, quenched QCD and QCD are identical. This implies that, in the effective field theory framework, some of the low energy constants in ( N c =3) quenched QCD and QCD are the same up to higher-order corrections in the 1/ N c expansion. Thus the calculation of the non-leptonic kaon decays relevant for the ΔI =1/2 rule in the quenched approximation is expected to differ from the unquenched one by an O (1/N c ) correction. However, the calculation relevant to the CP-violation parameter ϵ ′/ ϵ would have a relatively big higher-order correction due to the large cancellation in the leading order. Some important weak matrix elements are poorly known that even constraints with 100% errors are interesting. In those cases, quenched calculations will be very useful.