2,331 research outputs found
Taking into account the vertical drift of molecular ions when determining the kinetic parameters of ionization-recombination processes in the F2-layer maximum
Height distribution analysis for kinetic molecular ionization-recombination processes in F 2 region during solar activitie
The solitons redistribution in Bose-Einstein condensate in quasiperiodic optical lattice
We numerically study the dynamical excitations in Bose-Einstein condensate
(BEC) placed in periodic and quasi-periodic 2D optical lattice (OL). In case of
the repulsive mean-field interaction the BEC quantum tunnelling leads to a
progressive soliton's splitting and generating of secondary solitons, which
migrate to closest trapping potential minima. A nontrivial soliton dynamics
appears when a series of pi-pulses (phase kicks) are applied to the optical
lattice. Such sudden perturbation produces a dynamic redistribution of the
secondary solitons, leading to a formation of an artificial solitonic
superlattice. Different geometries of OL are analyzed.Comment: 16 pages, 6 figure
Ultrasoft Quark Damping in Hot QCD
We determine the quark damping rates in the context of next-to-leading order
hard-thermal-loop summed perturbation of high-temperature QCD where weak
coupling is assumed. The quarks are ultrasoft. Three types of divergent
behavior are encountered: infrared, light-cone and at specific points
determined by the gluon energies. The infrared divergence persists and is
logarithmic whereas the two others are circumvented.Comment: 16 page
Photon and electron spectra in hot and dense QED
Photon and electron spectra in hot and dense QED are found in the high
temperature limit for all |\q| using the Feynman gauge and the one-loop
self-energy. All spectra are split by the medium and their branches develop the
gap (the dynamical mass) at zero momentum. The photon spectrum has two branches
(longitudinal and transverse) with the common mass; but electron spectrum is
split on four branches which are well-separated for any |\q| including their
|\q|=0 limits (their effective masses). These masses and the photon thermal
mass are calculated explicitly and the different limits of spectrum branches
are established in detail. The gauge invariance of the high-temperature spectra
is briefly discussed.Comment: 9 pages, latex, no figure
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