1,418 research outputs found
Description of bulk observables in Au+Au collisions at top RHIC energy in the integrated HydroKinetic Model
The results on the main bulk observables obtained in the simulations within
the integrated hydrokinetic model (iHKM) of Au+Au collisions at the RHIC energy
GeV are presented along with the corresponding experimental
data from the STAR and the PHENIX collaborations. The simulations include all
the stages of the collision process: formation of the initial state, its
gradual thermalization and hydrodynamization, viscous relativistic
hydro-evolution, system's hadronization and particlization, and, finally, an
expansion of the interacting hadron-resonance gas. The model gives a
satisfactory description of charged-particle multiplicities, particle number
ratios, transverse momentum spectra for pions, kaons, protons and antiprotons,
charged-particle coefficients, and femtoscopy radii at all collision
centralities. It is demonstrated how one can estimate the times of the pion and
kaon maximal emission from the femto-scales.Comment: 17 pages, 14 figure
Description of bulk observables in Au+Au collisions at top RHIC energy in the integrated HydroKinetic Model
The results on the main bulk observables obtained in the simulations within
the integrated hydrokinetic model (iHKM) of Au+Au collisions at the RHIC energy
GeV are presented along with the corresponding experimental
data from the STAR and the PHENIX collaborations. The simulations include all
the stages of the collision process: formation of the initial state, its
gradual thermalization and hydrodynamization, viscous relativistic
hydro-evolution, system's hadronization and particlization, and, finally, an
expansion of the interacting hadron-resonance gas. The model gives a
satisfactory description of charged-particle multiplicities, particle number
ratios, transverse momentum spectra for pions, kaons, protons and antiprotons,
charged-particle coefficients, and femtoscopy radii at all collision
centralities. It is demonstrated how one can estimate the times of the pion and
kaon maximal emission from the femto-scales.Comment: 17 pages, 14 figure
DEVELOPMENT OF A SUBPROGRAM FOR ANALYZING PRODUCTION STRATEGY IN A COMPETITIVE ENVIRONMENT
In this article, we will explore market dynamics in competitive conditions, using examples of competitions involving three, eight, and fifteen manufacturers. We will compare their development strategies in terms of resource allocation between advertising and product quality. We will also discuss the benefits of market forecasting. Additionally, we will delve into the strategy of optimal resource allocation and provide examples of when it is advisable to adhere to it and when taking risks may lead to higher productivity and profit in a particular product line
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
Quantitative assessment of pinning forces and the superconducting gap in NbN thin films from complementary magnetic force microscopy and transport measurements
Epitaxial niobium-nitride thin films with a critical temperature of Tc=16K
and a thickness of 100nm were fabricated on MgO(100) substrates by pulsed laser
deposition. Low-temperature magnetic force microscopy (MFM) images of the
supercurrent vortices were measured after field cooling in a magnetic field of
3mT at various temperatures. Temperature dependence of the penetration depth
has been evaluated by a two-dimensional fitting of the vortex profiles in the
monopole-monopole model. Its subsequent fit to a single s-wave gap function
results in the superconducting gap amplitude Delta(0) = 2.9 meV = 2.1*kB*Tc, in
perfect agreement with previous reports. The pinning force has been
independently estimated from local depinning of individual vortices by lateral
forces exerted by the MFM tip and from transport measurements. A good
quantitative agreement between the two techniques shows that for low fields, B
<< Hc2, MFM is a powerful and reliable technique to probe the local variations
of the pinning landscape. We also demonstrate that the monopole model can be
successfully applied even for thin films with a thickness comparable to the
penetration depth.Comment: 6 pages, 6 figures, 2 table
Femtoscopy scales and particle production in the relativistic heavy ion collisions from Au+Au at 200 AGeV to Xe+Xe at 5.44 ATeV within the integrated hydrokinetic model
The recent results on the main soft observables, including hadron and photon
yields and particle number ratios, spectra, flow harmonics, as well as
the femtoscopy radii, obtained within the integrated hydrokinetic model (iHKM)
for high-energy heavy-ion collisions are reviewed and re-examined. The cases of
different nuclei colliding at different energies are considered: Au+Au
collisions at the top RHIC energy GeV, Pb+Pb collisions at
the LHC energies TeV and TeV, and the
LHC Xe+Xe collisions at TeV. The effect of the initial
conditions and the model parameters, including the utilized equation of state
(EoS) for quark-gluon phase, on the simulation results, as well as the role of
the final afterburner stage of the matter evolution are discussed. The possible
solution of the so-called ``photon puzzle'' is considered. The attention is
also paid to the dependency of the interferometry volume and individual
interferometry radii on the initial transverse geometrical size of the system
formed in the collision.Comment: 34 pages, 18 figure
Effect of diffusive boundaries on surface superconductivity in unconventional superconductors
Boundary conditions for a superconducting order parameter at a diffusive
scattering boundary are derived from microscopic theory. The results indicate
that for all but isotropic gap functions the diffusive boundary almost
completely suppresses surface superconductivity in the Ginzburg-Landau regime.
This indicates that in anisotropic superconductors surface superconductivity
can only be observed for surface normals along high symmetry directions where
atomically clean surfaces can be cleaved.Comment: Latex File, 12 pages, 2 Postscript figures, to appear in Phys. Rev. B
(June 1 1996
Space-time structure of particle emission and femtoscopy scales in ultrarelativistic heavy-ion collisions
The analysis of the spatiotemporal picture of particle radiation in
relativistic heavy-ion collisions in terms of correlation femtoscopy scales,
emission and source functions allows one to probe the character of evolution of
the system created in the collision. Realistic models, like the integrated
hydrokinetic model (iHKM), used in the present work, are able to simulate the
entire evolution process of strongly interacting matter produced in high-energy
nuclear collision. The mentioned model describes all the stages of the system's
evolution, including formation of the very initial state and its consequent
gradual thermalization, hydrodynamic expansion and afterburner hadronic
cascade, that can help researchers to figure out the specific details of the
process and better understand the formation mechanisms of certain observables.
In the current paper we investigate the behavior of the pion and kaon
interferometry radii and their connection with emission functions in
ultrarelativistic heavy-ion collisions at the Large Hadron Collider within
iHKM. We are focusing on the study of the emission time scales at different
energies for both particle species (pions and kaons) aiming to get deeper
insight into relation of these scales and the peculiarities of the mentioned
system's collective expansion and decay with the experimentally observed
femtoscopy radii. One of our main interests is the problem of the total
system's lifetime estimation based on the femtoscopy analysis.Comment: 28 pages, 9 figures. "Author edition" of the recently published
articl
HISTORICAL AND CULTURAL HERITAGE OF THE COUNTRY AS A RESOURCE FOR THE DEVELOPMENT OF MODERN TOURISM
The historical and cultural heritage of the country is exactly where to invest, and it will pay off after all, every country has buffets, swimming pools and sunbeds, and the historical and cultural heritage is something incredible and unique.
In terms of raising the level of education, the revival of the spirituality of the population becomes a historical and cultural heritage an influential factor in tourism development. This is especially true of Ukraine. After all, Ukraine has significant potential for the development of cultural and educational tourism, which is due primarily to a large number of unique historical and cultural monuments. Given the complex historical past and centuries-old coexistence of many peoples and religions, Ukraine has significant cultural and tourist potential
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