8,960 research outputs found
One-dimensional Ising model built on small-world networks: competing dynamics
In this paper, we offer a competing dynamic analysis of the one-dimensional
Ising model built on the small-world network (SWN). Adding-type SWNs are
investigated in detail using a simplified Hamiltonian of mean-field nature, and
the result of rewiring-type is given because of the similarities of these two
typical networks. We study the dynamical processes with competing Glauber
mechanism and Kawasaki mechanism. The Glauber-type single-spin transition
mechanism with probability p simulates the contact of the system with a heat
bath and the Kawasaki-type dynamics with probability 1-p simulates an external
energy flux. By studying the phase diagram obtained in the present work, we can
realize some dynamical properties influenced by the small-world effect.Comment: 5 pages, one figure, accepted for publication in Physical Review
Mean free paths and in-medium scattering cross sections of energetic nucleons in neutron-rich nucleonic matter within the relativistic impulse approximation
The mean free paths and in-medium scattering cross sections of energetic
nucleons in neutron-rich nucleonic matter are investigated using the nucleon
optical potential obtained within the relativistic impulse approximation with
the empirical nucleon-nucleon scattering amplitudes and the nuclear densities
obtained in the relativistic mean field model. It is found that the
isospin-splitting of nucleon mean free paths, sensitive to the imaginary part
of the symmetry potential, changes its sign at certain high kinetic energy. The
in-medium nucleon-nucleon cross sections are analytically and numerically
demonstrated to be essentially independent of the isospin asymmetry of the
medium and increase linearly with density in the high energy region where the
relativistic impulse approximation is applicable.Comment: 13 pages, 6 figure
Critical phenomena and thermodynamic geometry of charged Gauss-Bonnet AdS black holes
In this paper, we study the phase structure and equilibrium state space
geometry of charged topological Gauss-Bonnet black holes in -dimensional
anti-de Sitter spacetime. Several critical points are obtained in the canonical
ensemble, and the critical phenomena and critical exponents near them are
examined. We find that the phase structures and critical phenomena drastically
depend on the cosmological constant and dimensionality . The
result also shows that there exists an analogy between the black hole and the
van der Waals liquid gas system. Moreover, we explore the phase transition and
possible property of the microstructure using the state space geometry. It is
found that the Ruppeiner curvature diverges exactly at the points where the
heat capacity at constant charge of the black hole diverges. This black hole is
also found to be a multiple system, i.e., it is similar to the ideal gas of
fermions in some range of the parameters, while to the ideal gas of bosons in
another range.Comment: 17 pages, 8 figures, 3 table
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.Comment: 26 pages, 2 figures; minor revisio
Black hole solutions as topological thermodynamic defects
In this work, employing the generalized off-shell free energy, we treat black
hole solutions as defects in the thermodynamic parameter space. The results
show that the positive and negative winding numbers corresponding to the
defects indicate the local thermodynamical stable and unstable black hole
solutions, respectively. The topological number defined as the sum of the
winding numbers for all the black hole branches at an arbitrary given
temperature is found to be a universal number independent of the black hole
parameters. Moreover, this topological number only depends on the thermodynamic
asymptotic behaviors of the black hole temperature at small and large black
hole limits. Different black hole systems are characterized by three classes
via this topological number. This number could help us well understanding the
black hole thermodynamics, and further shed new light on the fundamental nature
of quantum gravity.Comment: 6 pages, 3 figure
A Transport Model for Nuclear Reactions Induced by Radioactive Beams
Major ingredients of an isospin and momentum dependent transport model for
nuclear reactions induced by radioactive beams are outlined. Within the IBUU04
version of this model we study several experimental probes of the equation of
state of neutron-rich matter, especially the density dependence of the nuclear
symmetry energy. Comparing with the recent experimental data from NSCL/MSU on
isospin diffusion, we found a nuclear symmetry energy of at subnormal densities. Predictions on
several observables sensitive to the density dependence of the symmetry energy
at supranormal densities accessible at GSI and the planned Rare Isotope
Accelerator (RIA) are also made.Comment: 10 pages. Talk given at the 2nd Argonne/MSU/JINA/INT RIA Workshop at
MSU, March 9-12, 2005 to be published in the Proceedings by the American
Institute of Physic
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