Low-Energy Qcd Nica/Mpd – Heavy-Ion Collider Project

Low-Energy Qcd Nica/Mpd – Heavy-Ion Collider Project

International Conference “Nuclear Science and its Application”, Samarkand, Uzbekistan, September 25-28, 2012 LOW-ENERGY QCD Musakhanov M.M. National University of Uzbekistan, Tashkent, Uzbekistan Phenomenology and lattice measurements of the QCD coupling αs (Q) at the region 0<Q<1 GeV show two options: 1. αs (Q) is a scale invariant (conformal behavior), which is essential to apply a property of conformal field theories (CFT) to the study of hadrons: the Anti-de-Sitter space/Conformal Field Theory (AdS/CFT) correspondence. 2. αs (Q) 0 at Q 0 and quasi- classical approximation to the QCD vacuum is applicable. This option is strongly supported by a number of lattice QCD studies. Quasi-classical QCD vacuum is a mixture of instantons and its constituents (instanton vacuum model). Since the integration measure over collective coordinates is invariant under permutation of constituents ‘belonging’ to different instantons, it allows instantons to overlap. This is a way for obtaining confinement. The momentum dependence of the dynamical quark mass measured at lattice perfectly coincids with the instanton vacuum model prediction with average instanton size ~ 0.33 fm and average inter-instanton distance R ~0.9 fm. We conclude that such an instantons are responsible for the Spontaneous Breaking of Chiral Symmetry (SBCS). We checked these assumptions by the evaluation the ChPT low-energy constants li with account of all 1/Nc corrections. We evaluated the m-dependence of Fπ, Mπ and extracted the constants l3 , l4 . The found that these values are in reasonable agreement with lattice results and phenomenological estimates. The calculated constant l7, representing mu – md ≠ 0 effects, is quite small and has a strong dependence on parameters of the model R , . It will be quite important to make a lattice estimation of this quantity. We conclude that instanton vacuum is a successful framework for hadron and nuclear physics having predictive power. NICA/MPD – HEAVY-ION COLLIDER PROJECT AT JINR (DUBNA) Vodopyanov A.S. Joint Institute for Nuclear Research, Dubna, Russia A new project NICA/MPD (Nuclotron-based Ion Collider fAcility /MultiPurposeDetector) is under development at JINR (Dubna, Russia). The main goal of the project is to create a universal facility for an experimental study of hot and dense strongly interacting matter and search for possible signs of the mixed phase and critical endpoint in heavy ion collisions. This goal will be reached in three steps: 1) Development of the existing NUCLOTRON accelerator facility as a basis for generation of intensive beams over atomic mass range from protons to gold and light polarized ions; 2) Design and construction of heavy ion collider NICA 25 Plenary Reports International Conference “Nuclear Science and its Application”, Samarkand, Uzbekistan, September 25-28, 2012 27 −2 −1 with the collision energy of √sNN = 4 ÷ 11 GeV and averaged luminosity of L = 10 cm s for Au (79+); 3) Design and construction of universal Multi-Purpose Detector at intersection region of the collider. The energy region to be studied on the NICA collider is of high interest since the highest baryonic density can be reached there. These investigations are relevant to understanding of the evolution of the Universe, neutron stars formation and physics of heavy ion collisions. Fig. 1 Artist view of the proposed NICA heavy-ion collider layout with Multi Purpose Detector and dedicated Spin Physics Detector. The NICA facility will consist of a cascade of accelerators. Multicharged ions will be generated in the unique ion source ”KRION” developed at JINR and accelerated in a linear accelerator up to 6 MeV per nucleon. They are then injected and accelerated in the Booster- Synchrotron, a new machine to be built, extracted and stripped on a carbon foil into ”bare state”. The booster magnetic system will be manufactured on the basis of the superferric magnets technology. First prototype magnets are already produced and tested. The ions are finally transferred to the NUCLOTRON where they are accelerated up to experiment energy. Before extraction the ion bunch is compressed to a length of 30 cm. Such ion bunches are injected, cycle by cycle, into the collider rings and provide the required luminosity in collisions. The accelerator chain includes: heavy ion source - RFQ injector - linac - booster ring - Nuclotron - Superconducting collider rings. The peak design kinetic energy of Au79+ ions in the collider is 4.5 A·GeV. Beam cooling and bunching systems are foreseen. It is foreseen that along with heavy ions NICA will provide proton and light ion beams including polarized beams. Fig. 2. Multi Purpose detector setup. 26 Plenary Reports International Conference “Nuclear Science and its Application”, Samarkand, Uzbekistan, September 25-28, 2012 The Central Detector will be built inside of the 1.0 T superconducting solenoid. The tracking will be provided by Time-Projection Chamber (TPC), End Cap Tracker and vertex tracker. The particle identification will be provided by TPC, Time-of-Flight (TOF) system and electromagnetic calorimeter. The Fast Forward Detectors will provide start signal for TOF. The energy of the projectile’s spectator nucleons will be measured by the Zero Degree Calorimeters (ZDC). MULTICOMPONENT (Ti-Zr-Hf-V-Nb)N NANOSTRUCTURE COATINGS FABRICATION, HIGH HARDNESS AND WEAR RESISTANCE Pogrebnjak A.D.1,2, Beresnev V.M.5, Kolesnikov D.A.6, Bondar O.V.1, Takeda Y.2, Oyoshi K.2, Shypylenko A.P.1,2, Kaverin M.V.1, Abrasonis G.3, Krause-Rehberg R.3,4, Andreev A.A.7, Karwat C.8 1Sumy State University, Sumy, Ukraine 2National Institute for Material Science, Tsukuba, Japan 3Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany 4Universität Halle, Institute für Physik, Halle, Germany 5Kharkov National University, Kharkov, Ukraine 6Belgorod State University, Belgorod, Russia 7Kharkov Physicotechnical Institute, Kharkov, Ukraine 8Lublin University of Technology, Lublin, Poland One of the most important tendencies of modern science is constructing of new materials, in particular, creation of multicomponent nanocomposite coatings with the grains characteristic dimensions between 2 and 50 nm. Nanocomposite coatings are a new generation of materials. They consist at least of two phases with nanocrystal and/or amorphous structure. Due to small (≤ 10 nm) grain size and more important role of surrounding boundary zones, nanocomposite materials act differently and show absolutely different properties in comparison with usual materials (with grain sizes ≥100 nm). Therefore, creation of new nanocomposite (nanostructure) coatings is an actual problem. In this work we studied the processes of impurities segregation on the boundaries of nanograins after finishing of the process of spinodal segregation. We used the unique methods of analysis: SEM with EDS, XRD, Nanoindentor, Test “Revest”, Positron Microbeam (Positron Annihilation), Microbeam (PIXE, RBS). Finally, we obtained solid multicomponent nanostructure coatings (Ti-Zr-Hf-V-Nb)N with high physical and mechanical properties 1. Pogrebnjak A.D., Shpak A.P., Azarenkov N.A., Beresnev V.M., Uspehi Fizicheskih Nauk 2009;179(1):35 2. Pogrebnjak A.D., Ponomarev A.G., Shpak A.P., Yu.A. Kunitskij. Uspehi Fizicheskih Nauk 2012;182 (3):287. 3. Beresnev V.M., Sobol’ O.V., Pogrebnjak A.D. et al., Problem of Atomic Science and Technology 2009;6:162. 27 Plenary Reports .

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