369 research outputs found
On foundations of quantum physics
Some aspects of the interpretation of quantum theory are discussed. It is
emphasized that quantum theory is formulated in the Cartesian coordinate
system; in other coordinates the result obtained with the help of the
Hamiltonian formalism and commutator relations between 'canonically conjugated'
coordinate and momentum operators leads to a wrong version of quantum
mechanics. The origin of time is analyzed in detail by the example of atomic
collision theory. It is shown that for a closed system like the three-body (two
nuclei + electron) time-dependent Schroedinger equation has no physical meaning
since in the high impact energy limit it transforms into an equation with two
independent time-like variables; the time appears in the stationary
Schroedinger equation as a result of extraction of a classical subsystem (two
nuclei) from a closed three-body system. Following the Einstein-Rozen-Podolsky
experiment and Bell's inequality the wave function is interpreted as an actual
field of information in the elementary form. The relation between physics and
mathematics is also discussed.Comment: This article is extended version of paper: Solov'ev, E.A.:
Phys.At.Nuc. v. 72, 853 (2009
Theoretical and numerical studies of wave-packet propagation in tokamak plasmas
Theoretical and numerical studies of wave-packet propagation are presented to
analyze the time varying 2D mode structures of electrostatic fluctuations in
tokamak plasmas, using general flux coordinates. Instead of solving the 2D wave
equations directly, the solution of the initial value problem is used to obtain
the 2D mode structure, following the propagation of wave-packets generated by a
source and reconstructing the time varying field. As application, the 2D WKB
method is applied to investigate the shaping effects (elongation and
triangularity) of tokamak geometry on the lower hybrid wave propagation and
absorbtion. Meanwhile, the Mode Structure Decomposition (MSD) method is used to
handle the boundary conditions and simplify the 2D problem to two nested 1D
problems. The MSD method is related to that discussed earlier by Zonca and Chen
[Phys. Fluids B 5, 3668 (1993)], and reduces to the well-known "ballooning
formalism" [J. W. Connor, R. J. Hastie, and J. B. Taylor, Phys. Rev. Lett. 40,
396 (1978)], when spatial scale separation applies. This method is used to
investigate the time varying 2D electrostatic ITG mode structure with a mixed
WKB-full-wave technique. The time varying field pattern is reconstructed and
the time asymptotic structure of the wave-packet propagation gives the 2D
eigenmode and the corresponding eigenvalue. As a general approach to
investigate 2D mode structures in tokamak plasmas, our method also applies for
electromagnetic waves with general source/sink terms, either by an
internal/external antenna or nonlinear wave interaction with zonal structures.Comment: 24 pages, 14 figure
Spectral Properties of Single Crystals of Synthetic Diamond
The half-width of the spectrum of Raman scattering (RS) of the first order of a diamond single crystal grown in a nickel-free system containing nitrogen getters is identical to all growth sectors (1.69 ±
0.02 cm−1). The sectorial inhomogeneity is not reflected in the transmission spectra and birefringence of this crystal. The nitrogen concentration is 4⋅1017 cm−3. For different growth sectors of the diamond crystal grown in the Ni–Fe–C system, the half-width of the Raman line varies from 1.74 to 2.08 cm−1,
differences in the transmission spectra and birefringence are observed, and photoluminescence is revealed. The concentration of nitrogen in the growth sectors {001} is 1.6⋅1019 cm−3, the content of nickel is estimated to be at a level of 1019 cm−3, and the content of nitrogen in the {111} sectors is 4⋅1019 cm−3
Hadronic Regge Trajectories: Problems and Approaches
We scrutinized hadronic Regge trajectories in a framework of two different
models --- string and potential. Our results are compared with broad spectrum
of existing theoretical quark models and all experimental data from PDG98. It
was recognized that Regge trajectories for mesons and baryons are not straight
and parallel lines in general in the current resonance region both
experimentally and theoretically, but very often have appreciable curvature,
which is flavor-dependent. For a set of baryon Regge trajectories this fact is
well described in the considered potential model. The standard string models
predict linear trajectories at high angular momenta J with some form of
nonlinearity at low J.Comment: 15 pages, 9 figures, LaTe
Dynamics of quantum systems
A relation between the eigenvalues of an effective Hamilton operator and the
poles of the matrix is derived which holds for isolated as well as for
overlapping resonance states. The system may be a many-particle quantum system
with two-body forces between the constituents or it may be a quantum billiard
without any two-body forces. Avoided crossings of discrete states as well as of
resonance states are traced back to the existence of branch points in the
complex plane. Under certain conditions, these branch points appear as double
poles of the matrix. They influence the dynamics of open as well as of
closed quantum systems. The dynamics of the two-level system is studied in
detail analytically as well as numerically.Comment: 21 pages 7 figure
ПРИМЕНЕНИЕ КОРРЕЛЯЦИОННОГО АНАЛИЗА ДВУМЕРНОГО CТОХАCТИЧЕCКОГО ПРОЦЕCCА ДЛЯ ОЦЕНКИ ЭКCПЛУАТАЦИОННОЙ ТЕХНОЛОГИЧНОCТИ ВЕРТОЛЕТА
The new calculated program complex which main task is to find the optimal algorithm of stochastic helicopter de- sign and assembling in terms of maintenance efficiency is described. It is shown that the use of the developed calculated program complex allows to efficiently solve the problems of helicopter construction with high-rating maintenance worka- bility factors.It is shown that for efficient problem solving connected with Maintenance and Repair costs reduction while heli- copter engineering and assembling in design office it is appropriate to use correlated analysis for maintenance workability estimation with the use of CAD system. The calculated program complex is based on mathematical apparatus of linear cor-related dependence of two-dimension (stochastic) process. The linear correlated dependence is considered as linear or anyconnection close to it between two variables for which the correlated analysis theorem is true.The algorithm of calculated program complex for helicopter maintenance workability estimation consists of five steps: choice of equipment that needs to be installed on the helicopter; correlation coefficient calculation for helicopters having this equipment and revealing of optimal variants of location; zone partition of the developed helicopter and analysis of possi- ble disposal of clusters in optimal order; disposal of clusters on the designed helicopter; correlation coefficient calculation, direct regression construction for the designed helicopter and comparison of these readings with helicopters-analogues. The calculation data of correlated analysis characteristics which indicate a possibility of increase of helicopter maintenance worka- bility level with a modicum of effort and time when working out the particular functional system is given.Описывается новый расчетный программный комплекс, в задачи которого входит поиск оптимального с точки зрения эффективности технической эксплуатации вертолетной техники алгоритма стохастического конструирования и компоновки вертолета. Показано, что использование разработанного расчетного программного комплекса позволяет успешно решать задачи обеспечения конструкции вертолета с высокими показателями эксплуатационной технологичности.Показано, что для успешного решения задач, связанных со снижением (на этапах эксплуатации) затрат на техническое обслуживание и ремонт при проектировании и компоновке вертолета в конструкторском бюро, целесообразно применение корреляционного анализа для оценки эксплуатационной технологичности совместно с ис-пользованием системы автоматизированного проектирования. За основу расчетного программного комплекса взятматематический аппарат линейной корреляционной зависимости двумерного (стохастического) процесса. Под ли-нейной корреляционной зависимостью понимается линейная или близкая к ней связь между двумя переменными,для которой справедлива теорема корреляционного анализа.Представлен алгоритм работы расчетного программного комплекса для оценки эксплуатационной техно-логичности вертолета, который состоит из пяти шагов: выбор оборудования, которое необходимо установить навертолет (блоки); подсчет коэффициента корреляции для вертолетов, имеющих данное оборудование и выявлениеоптимальных вариантов расположения; зональное деление разрабатываемого вертолета и анализ возможности раз-мещения блоков в оптимальном порядке; размещение блоков на проектируемом вертолете; подсчет коэффициентакорреляции, построение прямой регрессии для проектируемого вертолета и сравнение данных показателей с вер-толетами-аналогами. Приведены результаты расчета характеристик корреляционного анализа, которые свидетель-ствуют о потенциальной возможности повышения уровня эксплуатационной технологичности вертолета с мини-мальными затратами труда и времени при разработке отдельной функциональной системы
Quantum-mechanical and semiclassical study of the collinear three-body Coulomb problem: Inelastic collisions below the three-body disintegration threshold
Improved SOT (Hinode mission) high resolution solar imaging observations
We consider the best today available observations of the Sun free of
turbulent Earth atmospheric effects, taken with the Solar Optical Telescope
(SOT) onboard the Hinode spacecraft. Both the instrumental smearing and the
observed stray light are analyzed in order to improve the resolution. The Point
Spread Function (PSF) corresponding to the blue continuum Broadband Filter
Imager (BFI) near 450 nm is deduced by analyzing i/ the limb of the Sun and ii/
images taken during the transit of the planet Venus in 2012. A combination of
Gaussian and Lorentzian functions is selected to construct a PSF in order to
remove both smearing due to the instrumental diffraction effects (PSF core) and
the large-angle stray light due to the spiders and central obscuration (wings
of the PSF) that are responsible for the parasitic stray light. A
Max-likelihood deconvolution procedure based on an optimum number of iterations
is discussed. It is applied to several solar field images, including the
granulation near the limb. The normal non-magnetic granulation is compared to
the abnormal granulation which we call magnetic. A new feature appearing for
the first time at the extreme- limb of the disk (the last 100 km) is discussed
in the context of the definition of the solar edge and of the solar diameter. A
single sunspot is considered in order to illustrate how effectively the
restoration works on the sunspot core. A set of 125 consecutive deconvolved
images is assembled in a 45 min long movie illustrating the complexity of the
dynamical behavior inside and around the sunspot.Comment: 15 pages, 22 figures, 1 movi
On the mechanisms of superfluidity in atomic nuclei
A system of equations is obtained for the Cooper gap in nuclei. The system
takes two mechanisms of superfluidity into account in an approximation
quadratic in the phonon- production amplitude : a Bardeen- Cooper- Schrieffer
(BCS) type mechanism and a quasiparticle- phonon mechanism. These equations are
solved for 120 Sn in a realistic approximation. If the simple procedures
proposed are used to determine the new particle- particle interaction and to
estimate the average effect, then the contribution of the quasiparticle- phonon
mechanism to the observed width of the pairing gap is 26% and the BCS-type
contribution is 74%. This means that at least in semimagic nuclei pairing is of
a mixed nature - it is due to the two indicated mechanisms, the first being
mainly a surface mechanism and the second mainly a volume mechanism.Comment: 6 page
Resonance scattering and singularities of the scattering function
Recent studies of transport phenomena with complex potentials are explained
by generic square root singularities of spectrum and eigenfunctions of
non-Hermitian Hamiltonians. Using a two channel problem we demonstrate that
such singularities produce a significant effect upon the pole behaviour of the
scattering matrix, and more significantly upon the associated residues. This
mechanism explains why by proper choice of the system parameters the resonance
cross section is increased drastically in one channel and suppressed in the
other channel.Comment: 4 pages, 3 figure
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