8,505 research outputs found
Quantal Extension of Mean-Field Dynamics
A method is presented for numerical implementation of the extended TDHF
theory in which two-body correlations beyond the mean-field approximation are
incorporated in the form of a quantal collision term. The method is tested in a
model problem in which the exact solution can be obtained numerically. Whereas
the usual TDHF fails to reproduce the long time evolution, a very good
agreement is found between the extended TDHF and the exact solution.Comment: 22 Latex pages including 7 figure
Legal origin and the evolution of environmental quality
We extend the empirical literature on the environmental Kuznets curve (EKC) by showing the legal origin matters for the evolution of environmental quality. Using observations of ambient sulfur dioxide levels, we find that the EKC for French and British legal origin countries diverge as incomes rise, with the EKC for French legal origin countries lying significantly below that for countries of British legal origin. This finding is robust to the inclusion of proxies for democracy and corruption, the institutional variables emphasized in the current EKC literature. Our results are consistent with the idea that the British common law tradition places a greater emphasis on private relative to collective property rights.Environmental quality, institutions, legal origin. economic development, evironmental Kuznets curve
Nucleon exchange in heavy-ion collisions within stochastic mean-field approach
Nucleon exchange mechanism is investigated in deep-inelastic symmetric
heavy-ion collisions in the basis of the Stochastic Mean-Field approach. By
extending the previous work to off-central collisions, analytical expression is
deduced for diffusion coefficient of nucleon exchange mechanism. Numerical
calculations are carried out for Ca + Ca and Zr +
Zr systems and the results are compared with the phenomenological
nucleon exchange model. Also, calculations are compared with the available
experimental results of deep-inelastic collisions between calcium nuclei.Comment: 8 pages, 7 figure
Ultrafast dynamics of finite Hubbard clusters - a stochastic mean-field approach
Finite lattice models are a prototype for strongly correlated quantum systems
and capture essential properties of condensed matter systems. With the dramatic
progress in ultracold atoms in optical lattices, finite fermionic Hubbard
systems have become directly accessible in experiments, including their
ultrafast dynamics far from equilibrium. Here, we present a theoretical
approach that is able to treat these dynamics in any dimension and fully
includes inhomogeneity effects. The method consists in stochastic sampling of
mean-field trajectories and is found to be more accurate and efficient than
current nonequilibrium Green functions approaches. This is demonstrated for
Hubbard clusters with up to 512 particles in one, two and three dimensions
Superfluid fission dynamics with microscopic approaches
Recent progresses in the description of the latter stage of nuclear fission
are reported. Dynamical effects during the descent of the potential towards
scission and in the formation of the fission fragments are studied with the
time-dependent Hartree-Fock approach with dynamical pairing correlations at the
BCS level. In particular, this approach is used to compute the final kinetic
energy of the fission fragments. Comparison with experimental data on the
fission of 258Fm are made.Comment: Proceeding of the "International Conference on Nuclear Structure and
Related Topics" (NSRT15
Quantal description of nucleon exchange in stochastic mean-field approach
Nucleon exchange mechanism is investigated in central collisions of symmetric
heavy-ions in the basis of the stochastic mean-field approach. Quantal
diffusion coefficients for nucleon exchange are calculated by including
non-Markovian effects and shell structure. Variances of fragment mass
distributions are calculated in central collisions of Ca +
Ca, Ca + Ca and Ni + Ni systems
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