TOPOLOGICAL METHODS IN QUANTUM COMPUTATIONS

S.A. Duplij, I.I. Shapoval

Full Text :   (2500 kB, Rus.) 

Abstract
Basic concepts of quantum information theory, principles of quantum calculations and the possibility of creation on this basis unique on calculation power and functioning principle device, named quantum computer, are concerned. The main blocks of quantum logic, schemes of quantum calculations implementation, as well as some known today effective quantum algorithms, called to realize ad-vantages of quantum calculations upon classical, are presented here. Among them special place is taken by Shor's algorithm of num-ber factorization and Grover's algorithm of unsorted database search. Phenomena of decoherence, its influence on quantum computer stability and methods of quantum errors correction are described. Topological quantum computation conception is stated. It hasn't more computational power than the conventional quantum computation has, but is noiseless by its nature. Anyon statistics necessity for qubits is shown and representative anyon model of topological quantum information processing is presented.

KEY WORDS: quantum calculations, quantum algorithms, noise stability, decoherence, topological quantum calculations, theory of braids, anyons.

STRUCTURE OF THE ⁴⁶Ti NUCLEUS FROM (p,g) REACTION

I.D. Fedorets, S.S. Ratkevich

Full Text :   (1500 kB, Rus.) 

Abstract
The level structure of ⁴⁶Тi has been studied through the non-selective ⁴⁵Sc(p,g) reaction in the proton energy range E_p=1.2 - 3.1 MeV. The average resonance proton capture method has been applied to spin-parity assignments for states up to 5.5 MeV excitation energy ⁴⁶Тi. The radiative strength function of primary Е1-transitions, populating these states has been determined. The data so obtained are compared with predictions of various models. Comparison with ⁵⁰Cr, a cross-conjugate nucleus of ⁴⁶Тi, is also made. The observed states are interpreted within the frame of large scale shell model calculations in the full pf space (positive parity) and as particle-hole excitation from the d_3/2 shell (negative parity). For naturale parity states of ⁴⁶Тi, experimental data and shell model results are compared with those of the interacting boson model. The best description for E1 transitions is achieved on the base of the model accounting for the dependence of the strength function on the g-ray energy, temperature, and nuclear shell structure.

KEY WORDS: (p,g) reaction, average resonance method, dipole transitions, excitation states, radiative strength function, shell model, interacting boson model.

NONLINEAR SUPERSYMMETRIC CLASSICAL ELECTRODYNAMICS

S.A. Duplij, G.A. Goldin, V.M. Shtelen

Full Text :   (780 kB, Rus.) 

Abstract
In this paper we propose a general approach to nonlinear classical electrodynamics, allowing its description in the largest possible class of media (anisotropic, piroelectric, chiral, and ferromagnetic), and including both Lagrangian and non-Lagrangian (e.g., dissipative) theories.We introduce generalized constitutive equations via constitutive tensors of a very general form.We formulate electromagnetic duality in terms of these constitutive tensors. We also propose a supersymmetric generalization of the constitutive equations in a superfield approach.

KEY WORDS: constitutive equations, nonlinear electrodynamics, duality, supersymmetry, superfield.

EFFECT OF COLD ALPHA-PARTICLE REMOVAL AND FUELING SCENARIOS ON POWER AND PARTICLE BALANCE IN FUSION PLASMA

A.V. Eremin, A.A. Shishkin

Full Text :   (470 kB, Eng.) 

Abstract
Evolution in time of the plasma density, temperature and thermal alpha-particle density is considered under modeling of the helium ash removal. It is shown that slow changing in time of the helium ash density can be used for the operation path changing in fusion DT plasma. There is considered also the effect of different scenarios of fueling rates on the plasma operation path and steady state parameters. The temporal evolutions of the operating point during the ignition access and ignited operation phases are analyzed analytically and numerically. The main target of the study is the optimization of the plasma operation scenario in future fusion reactors including ITER.

KEY WORDS: fusion plasma, ignition and confinement, alpha-particles, time evolution, alpha-particle removal, fuel rates scenarios, ITER.

INFLUENCE OF SOLIDIFICATION CONDITIONS ON MACROSCOPIC CRYSTALLIZATION FRONT AND STRUCTURAL PERFECTION OF Ni-ALLOYS SINGLE CRYSTALS

V.M. Azhazha, V.J. Sverdlov, A.A. Kondratov, A.V. Boguslajev, V.V. Klochikhin

Full Text :   (4600 kB, Rus.) 

Abstract
The influence of solidification conditions (temperature gradient and direct solidification velocity) as well as alloyed elements concentration on macroscopic growth front of Ni-alloys NV-4 and ZS32-VI single crystals has been investigated. Experimentally obtained optimal parameters of growing single crystals with perfect structure correspond to a sharp form of macroscopic solidification front with a top in the form of separately growing dendrite cell. The relationship between the morphology of a cell structure and the form of macroscopic growth front of a single crystal, which are formed in the process of energy crystallization dissipation is analyzed.

KEY WORDS: Ni-alloys single crystal, macroscopic crystallization front, structural perfection, cell structure, self-organization.

PERCOLATION AND PHASE TRANSITION IN AMORPHOUS CARBON. MOLECULAR-DYNAMICAL SIMULATION

M.S. Byshkin, A.S. Bakai, A.A. Turkin

Full Text :   (300 kB, Rus.) 

Abstract
The molecular-dynamical investigation of amorphous carbon formed by quenching the melt is performed. The peculiarities are found on the pressure dependences of physical properties of amorphous carbon. It is shown, that these peculiarities are observed at the pressure value at which the percolation cluster of atoms in sp³ configuration arises and correlation of configurations of neighboring atoms changes in jump-like manner. The values of concentration of 4-fold coordinated atoms 30-40 % and pressure 13 GPa, at which the peculiarities are observed, are in a good agreement with results of other authors.

KEY WORDS: glass transition, percolation, phase transition, atom configuration, nanocrystal.

THE LINEARLY POLARIZED PHOTON BEAMS FOR PHOTONUCLEAR INVESTIGATIONS AT LOW ENERGY FACILITIES

V.B. Ganenko, G.A. Vashenko, D.D. Burdeinyi

Full Text :   (370 kB, Eng.) 

Abstract
Intensity and polarization spectra of Coherent Bremsstrahlung (CB) for the low-energy facility at MAX-lab and designed facility of NSC KIPT (project NESTOR) with the maximal energies of beam 250 and 160 MeV respectively are calculated. It is shown, that at the definite conditions of forming the beam is possible to obtain the CB beams with intensity and polarization, sufficient for conducting of experimental researches in the interval of energies of photons about 100 MeV for the maximal electron energy about 250 MeV, and in interval about 60 MeV on the beam line with the maximal electron energy about 160 MeV.

KEY WORDS: coherent bremsstrahlung, polarized photon beam.

THE EXPERIMENTAL INVISTIGATION OF ELECTRON CURRENT TIME INCREASING IN MAGNETRON GUN WITH SECONDARY EMISSION CATHODE

N.I. Ayzatskiy, A.N. Dovbnya, V.V. Zakutin, N.G. Reshetnyak, V.P. Romas’ko, I.A. Chertishchev, T.A. Kovalenko

Full Text :   (670 kB, Rus.) 

Abstract
The investigation of electron beam generation in magnetron gun with Al and Cu secondary emission cathods was carried out. It was shown that impulse duration is limited by desorbtion prosseses from cathode surface. It was shown that beam amplitude characteristics from Al and Cu cathods are similar. Dependence of electron current time increasing under magnetic field distribution was research. It was shown that minimum duratation time increasing takes place at uniform distribution of magnetic field.

KEY WORDS: electron bean, magnetron gun, secodary-emission cathode, time increasing of the beam current.

ABOUT THEORETICAL APPROACHES IN CONSTRUCTION LAGRANGE FUNCTION OF INDUSTRIAL SYSTEM

V.P.Demutskij, O.M.Pignastyj, V.D.Khodusov

Full Text :   (340 kB, Rus.) 

Abstract
In phase technological space the state of industrial system is determined. The "know-how" is set by a normative technological trajectory. Technological process on each technological operation is submitted by technology factors with normative parameters of manufacture and permissible deviations from them. With use of variational and differential principles Lagrange's function of industrial system is written down. Distinctions in the variational and differential approach are shown at construction of Lagrange's function of industrial systems. The equations of movement of subjects of work in the phase technological space, expenses connecting among themselves and rate of movement of preparations along a technological chain of industrial system are received. Integrals of movement are determined at the description of industrial systems.

KEY WORDS: synergetric, base product, the microscopic description, Lagrange's function, Euler's equations.

ESTAFETTE OF DRIFT RESONANCES IN TOKAMAK CONFIGURATION WITH REVERSED-SHEAR

S.V. Ivko, A.A. Shishkin

Full Text :   (370 kB, Eng.) 

Abstract
Induced particle transport by applying perturbations of the magnetic field with low poloidal "wave" numbers is studied by means of computer simulations. Reversed-shear operation regime for tokamaks is considered. The dependence of drift rotational angle transform profile on particle energy is calculated. The range of particle energies corresponding to reversed shear profile is defined. The removal of helium test particle from the plasma core to the periphery is demonstrated.

KEY WORDS: particle motion control, estafette of drift resonances, reversed shear tokamak, guiding center equations, computer simulation.