4,003 research outputs found
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 GeV in comparison with hadron-nuclear collisions at close
energies. The decreasing results in power dependence of distance variable on
collision energy for range 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
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FABRIC: A National-Scale Programmable Experimental Network Infrastructure
FABRIC is a unique national research infrastructure to enable cutting-edge and exploratory research at-scale in networking, cybersecurity, distributed computing and storage systems, machine learning, and science applications. It is an everywhere-programmable nationwide instrument comprised of novel extensible network elements equipped with large amounts of compute and storage, interconnected by high speed, dedicated optical links. It will connect a number of specialized testbeds for cloud research (NSF Cloud testbeds CloudLab and Chameleon), for research beyond 5G technologies (Platforms for Advanced Wireless Research or PAWR), as well as production high-performance computing facilities and science instruments to create a rich fabric for a wide variety of experimental activities
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
Using mosaic crystals for the generation of intense X-ray beams
The parametric X-ray (PXR) yield due to 500-MeV electrons in a 2-mm-thick diamond crystal with a mosaicity angle of ~0.2 mrad has been studied. It is shown that the mosaic crystal structure leads to a significant (about fourfold) increase in the PXR yield doe to the contribution of diffracted bremsstrahlung radiationye
Probing the deuteron structure at small N-N distances by cumulative pion production
The fragmentation of deuterons into pions emitted forward in the kinematic
region forbidden for free nucleon-nucleon collisions is analyzed. It is shown
that the inclusion of the non-nucleonic degrees of freedom in a deuteron
results in a satisfactory description of the data for the inclusive pion
spectrum and improves the description of the data about . According to
the data, has very small positive values, less than 0.2, which
contradicts the theoretical calculations ignoring these degrees of freedom.Comment: 3 pages, 2 postscript figures; to appear in the proceedings of
Conference on Quarks and Nuclear Physics (QNP 2002), Julich, Germany, 9-14
Jun 200
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
Using Semantic Web Technologies to Query and Manage Information within Federated Cyber-Infrastructures
Using Semantic Web Technologies to Query and Manage Information within Federated Cyber-Infrastructures
On QCD -evolution of Deuteron Structure Function for
The deep-inelastic deuteron structure function (SF) in the
covariant approach in light-cone variables is considered. The and
-dependences of SF are calculated. The QCD analysis of generated data both
for non-cumulative ranges was performed. It was
shown that -evolution of SF is valid for ranges and
for the same value of QCD scale parameter . It was
found the -dependence of SF for the ranges is essentially different.Comment: LaTeX, 10 pages, 2 Postscript figure
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