63,467 research outputs found
Rational Approximate Symmetries of KdV Equation
We construct one-parameter deformation of the Dorfman Hamiltonian operator
for the Riemann hierarchy using the quasi-Miura transformation from topological
field theory. In this way, one can get the approximately rational symmetries of
KdV equation and then investigate its bi-Hamiltonian structure.Comment: 14 pages, no figure
An improved single particle potential for transport model simulations of nuclear reactions induced by rare isotope beams
Taking into account more accurately the isospin dependence of nucleon-nucleon
interactions in the in-medium many-body force term of the Gogny effective
interaction, new expressions for the single nucleon potential and the symmetry
energy are derived. Effects of both the spin(isospin) and the density
dependence of nuclear effective interactions on the symmetry potential and the
symmetry energy are examined. It is shown that they both play a crucial role in
determining the symmetry potential and the symmetry energy at supra-saturation
densities. The improved single nucleon potential will be useful for simulating
more accurately nuclear reactions induced by rare isotope beams within
transport models.Comment: 6 pages including 6 figures
Deterministic generation of arbitrary photonic states assisted by dissipation
A scheme to utilize atom-like emitters coupled to nanophotonic waveguides is
proposed for the generation of many-body entangled states and for the
reversible mapping of these states of matter to photonic states of an optical
pulse in the waveguide. Our protocol makes use of decoherence-free subspaces
(DFS) for the atomic emitters with coherent evolution within the DFS enforced
by strong dissipative coupling to the waveguide. By switching from subradiant
to superradiant states, entangled atomic states are mapped to photonic states
with high fidelity. An implementation using ultracold atoms coupled to a
photonic crystal waveguide is discussed.Comment: 15 pages, 4 figure
Alfven seismic vibrations of crustal solid-state plasma in quaking paramagnetic neutron star
Magneto-solid-mechanical model of two-component, core-crust, paramagnetic
neutron star responding to quake-induced perturbation by differentially
rotational, torsional, oscillations of crustal electron-nuclear solid-state
plasma about axis of magnetic field frozen in the immobile paramagnetic core is
developed. Particular attention is given to the node-free torsional
crust-against-core vibrations under combined action of Lorentz magnetic and
Hooke's elastic forces; the damping is attributed to Newtonian force of shear
viscose stresses in crustal solid-state plasma. The spectral formulae for the
frequency and lifetime of this toroidal mode are derived in analytic form and
discussed in the context of quasi-periodic oscillations of the X-ray outburst
flux from quaking magnetars. The application of obtained theoretical spectra to
modal analysis of available data on frequencies of oscillating outburst
emission suggests that detected variability is the manifestation of crustal
Alfven's seismic vibrations restored by Lorentz force of magnetic field
stresses.Comment: 10 pages, 10 figure
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