8,919 research outputs found
Pion Polarizability in the NJL model and Possibilities of its Experimental Studies in Coulomb Nuclear Scattering
The charge pion polarizability is calculated in the Nambu-Jona-Lasinio model,
where the quark loops (in the mean field approximation) and the meson loops (in
the approximation) are taken into account. We show that quark loop
contribution dominates, because the meson loops strongly conceal each other.
The sigma-pole contribution plays the main role and
contains strong t-dependence of the effective pion polarizability at the region
. Possibilities of experimental test of this sigma-pole
effect in the reaction of Coulomb Nuclear Scattering are estimated for the
COMPASS experiment.Comment: 11 pages, 8 figure
Strongly coupled quantum discrete Liouville theory. I: Algebraic approach and duality
The quantum discrete Liouville model in the strongly coupled regime, 1<c<25,
is formulated as a well defined quantum mechanical problem with unitary
evolution operator. The theory is self-dual: there are two exponential fields
related by Hermitean conjugation, satisfying two discrete quantum Liouville
equations, and living in mutually commuting subalgebras of the quantum algebra
of observables.Comment: Latex2e, 20 page
Singularities inside non-Abelian black holes
Singularities inside static spherically symmetric black holes in the SU(2)
Einstein-Yang-Mills and Einstein-Yang-Mills-dilaton theories are investigated.
Analytical formulas are presented describing oscillatory and power law metric
behavior near spacelike singularities in generic solutions.Comment: REVTeX, 9 pages, 2 EPS figures, uses epsf.st
1/N_c- expansion of the quark condensate at finite temperature
Previously the quark and meson properties in a many quark system at finite
temperature have been studied within effective QCD approaches in the Hartree
approximation. In the present paper we consider the influence of the mesonic
correlations on the quark self-energy and on the quark propagator within a
systematic - expansion. Using a general separable ansatz for the
nonlocal interaction, we derive a selfconsistent equation for the
correction to the quark propagator. For a separable model with cut-off
formfactor, we obtain a decrease of the condensate of the order of 20\% at zero
temperature. A lowering the critical temperature for the onset of the chiral
restoration transition due to the inclusion of mesonic correlations is obtained
what seems to be closer to the results from lattice calculations.Comment: 19 pages, REVTeX, 5 figure
Energy Resolved Supercurrent between two superconductors
In this paper I study the energy resolved supercurrent of a junction
consisting of a dirty normal metal between two superconductors. I also consider
a cross geometry with two additional arms connecting the above mentioned
junction with two normal reservoirs at equal and opposite voltages. The
dependence of the supercurrent between the two superconductors on the applied
voltages is studied.Comment: revtex, 7 pages, 8 figures. accepted by Phys. Rev.
Condensation of Silica Nanoparticles on a Phospholipid Membrane
The structure of the transient layer at the interface between air and the
aqueous solution of silica nanoparticles with the size distribution of
particles that has been determined from small-angle scattering has been studied
by the X-ray reflectometry method. The reconstructed depth profile of the
polarizability of the substance indicates the presence of a structure
consisting of several layers of nanoparticles with the thickness that is more
than twice as large as the thickness of the previously described structure. The
adsorption of 1,2-distearoyl-sn-glycero-3-phosphocholine molecules at the
hydrosol/air interface is accompanied by the condensation of anion silica
nanoparticles at the interface. This phenomenon can be qualitatively explained
by the formation of the positive surface potential due to the penetration and
accumulation of Na+ cations in the phospholipid membrane.Comment: 7 pages, 5 figure
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