Collective and fractal properties of pion jets in the four-velocity space at intermediate energies

Experimental results are presented for study of collective and fractal properties of soft pion jets in the space of relative four-dimensional velocities. Significant decreasing is obtained for mean square of second particle distances from jet axis for pion-proton interactions at initial energies $\sim 3$ GeV in comparison with hadron-nuclear collisions at close energies. The decreasing results in power dependence of distance variable on collision energy for range $\sim 2 - 4$ GeV. The observation allows us to estimate the low boundary of manifestation of color degree of freedom in pion jet production. Cluster dimension values were deduced for pion jets in various reactions. Fractional values of this dimension indicate on the manifestation of fractal-like properties by pion jets. Changing of mean kinetic energy of jet particles and fractal dimension with initial energy increasing is consistent with suggestion for presence of color degrees of freedom in pion jet production at intermediate energies.Comment: The conference "Physics of fundamental interactions". ITEP, Moscow, Russia. November 23 - 27, 200

On QCD Q2Q^2-evolution of Deuteron Structure Function F2D(xD,Q2)F_2^D(x_D,Q^2) for xD>1x_D>1

The deep-inelastic deuteron structure function (SF) $F_2^D(x_D,Q^2)$ in the covariant approach in light-cone variables is considered. The $x_D$ and $Q^2$-dependences of SF are calculated. The QCD analysis of generated data both for non-cumulative $x_D1$ ranges was performed. It was shown that $Q^2$-evolution of SF is valid for ranges $0.275<x_D<0.85$ and $1.1<x_D<1.4$ for the same value of QCD scale parameter ${\Lambda}$. It was found the $x_D$-dependence of SF for the ranges is essentially different.Comment: LaTeX, 10 pages, 2 Postscript figure

Enabling comparison of UrQMD with Geant4 hadronic models

Geant4 has an abundant set of physics models that handle the diverse interaction of particles with matter across a wide energy range. However, there are also many well established reaction codes currently used in the same fields where Geant4 is applied. One such code is the Ultra-relativistic Quantum Molecular Dynamics (UrQMD) model. In order to take advantage of the UrQMD code, we create a tool to enable comparisons among UrQMD and Geant4 hadronic models. This tool allows a user to process the output file of UrQMD through Geant4 toolkit, while at the same time, can choose among different Geant4 hadronic model generators. As an example, the UrQMD model is compared with the HARP-CDP experimental data and with the Binary and FRITIOF generators, in the framework of Geant4. It is shown that the UrQMD model can better reproduce charged pion production for p+Cu and Pb interactions at 3, 8 and 15 GeV/c, and is a good candidate for Geant4 hadronic models.Comment: 17 pages, 5 Figure

The system of human resource development in energy saving in the Ural region

A system of education in the field of energy saving has been developed, built and successfully used for a number of years in the Ural region. In the Ural Federal University (UrFU) the "Energy Saving" Department and Regional Learning and Teaching Centre were created in 1999. At the present time more than 2000 senior students of ten institutes and of a number of UrFU territorial branches listen to lectures and study energy saving and energy efficiency issues at the practical studies yearly at the "Energy Saving" Department. In teaching the above mentioned disciplines a problematic-topical approach is used. It promotes forming a high level of concern and motivation among students to study and master the bases of theoretical and practical activity, enabling them to get the most actual and reliable information. Employees of the department have prepared and published a considerable volume of courseware and scientific-andtechnological literature on the problems of energy saving and raising efficiency of energy usage, forming an academic system, which includes different levels and types of knowledge, methods of educating. Masters' preparing has been started together with the department "Atomic power stations and renewable energy sources" with the deepened studying energy saving and energy efficiency issues. Taking this experience into account, an education standard of UrFU "Energy saving and energy efficiency raising in industry and budget sphere". Thus, a complex approach for creating and constantly improving the system of energy saving specialists' preparation has been realized and is being developed in the territory of the Ural region. © 2014 WIT Press.International Journal of Safety and Security Engineering;International Journal of Sustainable Development and Planning;WIT Transactions on Ecology and the Environmen

Jet Energy Density in Hadron-Hadron Collisions at High Energies

The average particle multiplicity density dN/deta is the dynamical quantity which reflects some regularities of particle production in low-pT range. The quantity is an important ingredient of z-scaling. Experimental results on charged particle density are available for pp, pA and AA collisions while experimental properties of the jet density are still an open question. The goal of this work is to find the variable which will reflect the main features of the jet production in low transverse energy range and play the role of the scale factor for the scaling function psi(z) and variable z in data z-presentation. The appropriate candidate is the variable we called "scaled jet energy density". Scaled jet energy density is the probability to have a jet with defined ET in defined xT and pseudorapidity regions. The PYTHIA6.2 Monte Carlo generator is used for calculation of scaled jet energy density in proton-proton collisions over a high energy range (sqrt s = 200-14000 GeV) and at eta = 0. The properties of the new variable are discussed and sensitivity to "physical scenarios" applied in the standard Monte Carlo generator is noted. The results of scaled jet energy density at LHC energies are presented and compared with predictions based on z-scaling.Comment: 11 pages, LaTeX, 8 figures, Presented at the XVII International Baldin Seminar on High Energy Physics Problems "Relativistic Nuclear Physics & Quantum Chromodynamics", Dubna, Russia, September 27 - October 2, 200

Energy Storage in a Hamiltonian System in Partial Contact with a Heat Bath

To understand the mechanism allowing for the long-term storage of excess energy in proteins, we study a Hamiltonian system consisting of several coupled pendula in partial contact with a heat bath. It is found that energy storage is possible when the motion of each pendulum switches between oscillatory (vibrational) and rotational (phase-slip) modes. The storage time increases almost exponentially to the square root of the injected energy. The relevance of our mechanism to protein motors is discussed.Comment: 8 pages, 4 figures, to appear in J.Phys.Soc.Jp

Subthreshold and near-threshold kaon and antikaon production in proton-nucleus reactions

The differential production cross sections of K^+ and K^- mesons have been measured at the ITEP proton synchrotron in p+Be, p+Cu collisions under lab angle of 10.5^0, respectively, at 1.7 and 2.25, 2.4 GeV beam energies. A detailed comparison of these data with the results of calculations within an appropriate folding model for incoherent primary proton-nucleon, secondary pion-nucleon kaon and antikaon production processes and processes associated with the creation of antikaons via the decay of intermediate phi mesons is given. We show that the strangeness exchange process YN->NNK^- gives a small contribution to the antikaon yield in the kinematics of the performed experiment. We argue that in the case when antikaon production processes are dominated by the channels with KK^- in the final state, the cross sections of the corresponding reactions are weakly influenced by the in-medium kaon and antikaon mean fields.Comment: 24 pages. accepted for publication at J.Phys.