1,475 research outputs found
Direct observation of superconducting vortex clusters pinned by a periodic array of magnetic dots in ferromagnetic/superconducting hybrid structures
Strong pinning of superconducting flux quanta by a square array of 1
m-sized ferromagnetic dots in a magnetic-vortex state was visualized by
low-temperature magnetic force microscopy (LT-MFM). A direct correlation of the
superconducting flux lines with the positions of the dots was derived. The
force that the MFM tip exerts on the individual vortex in the depinning process
was used to estimate the spatial modulation of the pinning potential. It was
found, that the superconducting vortices which are preferably located on top of
the Py dots experience about 15 times stronger pinning forces as compared to
the pinning force in the pure Nb film. The strong pinning exceeds the repulsive
interaction between the superconducting vortices and allows the vortex clusters
to be located at each dot. Our microscopic studies are consistent with global
magnetoresistace measurements on these hybrid structures.Comment: 4 pages, 4 figure
Femtoscopy correlations of kaons in collisions at LHC within hydrokinetic model
We provide, within the hydrokinetic model, a detailed investigation of kaon
interferometry in collisions at LHC energy (
TeV). Predictions are presented for 1D interferometry radii of and
pairs as well as for 3D femtoscopy scales in out, side and
long directions. The results are compared with existing pion interferometry
radii. We also make predictions for full LHC energy.Comment: 12 pages, 6 figure
Tubular initial conditions and ridge formation
The 2D azimuth & rapidity structure of the two-particle correlations in
relativistic A+A collisions is altered significantly by the presence of sharp
inhomogeneities in superdense matter formed in such processes. The causality
constraints enforce one to associate the long-range longitudinal correlations
observed in a narrow angular interval, the so-called (soft) ridge, with
peculiarities of the initial conditions of collision process. This study's
objective is to analyze whether multiform initial tubular structures,
undergoing the subsequent hydrodynamic evolution and gradual decoupling, can
form the soft ridges. Motivated by the flux-tube scenarios, the initial energy
density distribution contains the different numbers of high density tube-like
boost-invariant inclusions that form a bumpy structure in the transverse plane.
The influence of various structures of such initial conditions in the most
central A+A events on the collective evolution of matter, resulting spectra,
angular particle correlations and v_n-coefficients is studied in the framework
of the HydroKinetic Model (HKM).Comment: 18 pages, 6 figures, the paper to be published in Advances of High
Energy Physics (2013, in press
Vortex phases in mesoscopic cylinders with suppressed surface superconductivity
Vortex structures in mesoscopic cylinder placed in external magnetic field
are studied under the general de Gennes boundary condition for the order
parameter corresponding to the suppression of surface superconductivity. The
Ginzburg-Landau equations are solved based on trial functions for the order
parameter for vortex-free, single-vortex, multivortex, and giant vortex phases.
The equilibrium vortex diagrams in the plane of external field and cylinder
radius and magnetization curves are calculated at different values of de Gennes
"extrapolation length" characterizing the boundary condition for the order
parameter. The comparison of the obtained variational results with some
available exact solutions shows good accuracy of our approach.Comment: RevTex, 11 pages, 10 figure
Validity and limitations of the median-line integral equation technique in the scattering by material strips of sub-wavellength thickness
Cataloged from PDF version of article.Considered is the 2-D scattering of a plane wave by a thin flat material strip. The data obtained by using the empirical method of generalized boundary conditions and singular integral equations on the strip median line are compared with the results of solving the Muller boundary integral equation that takes full account of strip thickness. Discretization of integral equations in both cases is performed using the Nystrom methods that lead to convergent algorithms. Numerical results cover E and H polarizations and two types of thin strips: conventional dielectric and metal in the optical range. The validity and limitations of approximate model are established and discussed
Technological progress in operation of multiservice sport centers viewed as management issue
Objective of the study was to consider benefits of social technologies in application to the modern multiservice sport center (MSC) management systems. To analyze the factors and conditions of effect on the MSC service progress, we performed a questionnaire survey of the MSC clientele and service personnel in July-October 2015 in the Belgorod regio
NATURAl, HISTORICAL AND CULTURAL BRANDS IN UKRAINE
Place branding is a sphere where such things as templates, borders or even copies are not required. The idea of the brand must correspond to the singularity of a certain territory or place. Therefore, forming the brand of the territory requires taking into consideration such important factors as originality, uniqueness, and complexity of copying. The better the individuality of this place is shown in its image, the better its perception by potential tourists to be interested in. It should be emphasized that the brand of the place cannot be implanted as its values are identified by professionals from various fields. And the most important thing comprises the fact that the brand must be based only on real features
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