77 research outputs found
P- and T-violation Tests with Polarized Resonance Neutrons
The enhancements of CP-violating effects in resonance neutron
transmissionthrough polarized targets are studied for 2 possible versions of
experiment. The importance is stressed of error analysis and of pseudomagnetic
effects' compensation.Comment: 11 pages, LaTeX + 4 PostScript figure
Distinctive Features of the Phase Composition of Porous TiNi-based Alloys Obtained by Reaction and Diffusion Sintering
The present article is concerned with questions of reaction and diffusion sintering of porous shape-memory TiNi-based alloys. The comparative analysis of structural features of the porous alloys obtained by diffusion sintering of TiNi powder and reaction sintering of Ti and Ni powders was conducted. It is observed that the main feature of structure of the porous alloys is related to fraction of the TiNi phase which occupies about 90 vol.% at diffusion sintering, and 20÷50 % of the total volume of multiphase alloy for reaction sintering. The mechanisms of the structure formation on the solid phase and liquid phase sintering stages of these methods were considered. The role of Ti2Ni phase during sintering was disclosed. The Ti2Ni phase not only provides the necessary quality of sintering, activates recrystallization processes for diffusion sintering, modifies the phase composition of the sintered specimen for reaction sintering, but also participates in the formation of the TiNi phase, increasing its fraction
Crystallization Features of Porous TiNi Made by SHS
The surface layers and fracture surfaces of porous titanium nickelide obtained by self-propagating high temperature synthesis (SHS) in a flow reactor in an argon atmosphere are studied by SEM and energy dispersive analysis. It is alleged that primary pores 5–15 µ in size and the related granular layer are formed due to segregation and capillary force effect during peritectic crystallization of some porous alloy areas. Coarsening and deformation of pores, as well as migration and growth of granular layers, is caused by reaction gases. Carbon and oxygen impurities present in the reaction gases and the protective atmosphere penetrate into the melt film on the pore surface to form strong and corrosion-resistant nanostructured layers of intermetallic carbides, nitrides and oxides
Structure and Application of ATDP Suite for Electronic System States Detection and Evolution Operator Restoration
Structure and peculiarities of the Adaptive Testing Data Processing software Suite (ATDP Suite) are presented. It is applied for dynamic characteristics restoration from experimental time series of nonlinear and unstable electronic system. Basic methods realized in ATDP Suite are demonstrated. Application of ATDP Suite for electromagnetic tests of microwave receivers demonstrated the possibility to analyze and interpret the dynamic characteristics of complex nonlinear system.Представлены структура и особенности программного пакета адаптивной тестирующей обработки данных (ATDP Suite). Он применен к восстановлению динамических характеристик из экспериментальных временных рядов нелинейной и нестабильной электронной системы. Продемонстрированы основные методы, реализованные в ATDP Suite. Применение ATDP Suite для электромагнитного тестирования СВЧ приемников показало возможность анализировать и интерпретировать динамические характеристики сложной нелинейной системы.Представлено структуру та особливості програмного пакета адаптивної тестуючої обробки даних (ATDP Suite). Його застосовано для відтворення динамічних характеристик з експериментальних часових рядів нелінійної та нестабільної електронної системи. Продемонстровано основні методи, реалізовані в ATDP Suite. Застосування ATDP Suite для електромагнітного тестування НВЧ приймачів продемонструвало можливість аналізувати та інтерпретувати динамічні характеристики складної нелінійної системи
Neutrino mediated muon--electron conversion in nuclei revisited
The non-photonic neutrino exchange mechanism of the lepton flavor violating
muon-electron conversion in nuclei is revisited. First we determine the nucleon
coupling constants for the neutrino exchange mechanism in a relativistic quark
model taking into account quark confinement and chiral symmetry requirements.
This includes a new, previously overlooked tree-level contribution from
neutrino exchange between two quarks in the same nucleon. Then for the case of
an additional sterile neutrino we reconsider the coherent mode of this process.
The presence of a mixed sterile-active neutrino state heavier than the quark
confinement scale Lambda_c (~1 GeV) may significantly improve the prospects for
observation of this process in future experiments as compared to the
conventional scenario with only light neutrinos. Turning the arguments around
we derive new experimental constraints on |U_(mu h)| and |U_(e h)| mixing
matrix elements from the non-observation of muon--electron conversion.Comment: 13 pages, RevTex, 1 Postscript figur
-Strands
A -strand is a map for a Lie
group that follows from Hamilton's principle for a certain class of
-invariant Lagrangians. The SO(3)-strand is the -strand version of the
rigid body equation and it may be regarded physically as a continuous spin
chain. Here, -strand dynamics for ellipsoidal rotations is derived as
an Euler-Poincar\'e system for a certain class of variations and recast as a
Lie-Poisson system for coadjoint flow with the same Hamiltonian structure as
for a perfect complex fluid. For a special Hamiltonian, the -strand is
mapped into a completely integrable generalization of the classical chiral
model for the SO(3)-strand. Analogous results are obtained for the
-strand. The -strand is the -strand version of the
Bloch-Iserles ordinary differential equation, whose solutions exhibit dynamical
sorting. Numerical solutions show nonlinear interactions of coherent wave-like
solutions in both cases. -strand equations on the
diffeomorphism group are also introduced and shown
to admit solutions with singular support (e.g., peakons).Comment: 35 pages, 5 figures, 3rd version. To appear in J Nonlin Sc
The Fourth Standard Model Family and the Competition in Standart Model Higgs Boson Search at Tevatron and LHC
The impact of the fourth Standard Model family on Higgs boson search at
Tevatron and LHC is reviewed.Comment: 7 pages, 13 figure
Abelian Toda field theories on the noncommutative plane
Generalizations of GL(n) abelian Toda and abelian affine
Toda field theories to the noncommutative plane are constructed. Our proposal
relies on the noncommutative extension of a zero-curvature condition satisfied
by algebra-valued gauge potentials dependent on the fields. This condition can
be expressed as noncommutative Leznov-Saveliev equations which make possible to
define the noncommutative generalizations as systems of second order
differential equations, with an infinite chain of conserved currents. The
actions corresponding to these field theories are also provided. The special
cases of GL(2) Liouville and sinh/sine-Gordon are
explicitly studied. It is also shown that from the noncommutative
(anti-)self-dual Yang-Mills equations in four dimensions it is possible to
obtain by dimensional reduction the equations of motion of the two-dimensional
models constructed. This fact supports the validity of the noncommutative
version of the Ward conjecture. The relation of our proposal to previous
versions of some specific Toda field theories reported in the literature is
presented as well.Comment: v3 30 pages, changes in the text, new sections included and
references adde
Classical/quantum integrability in AdS/CFT
We discuss the AdS/CFT duality from the perspective of integrable systems and
establish a direct relationship between the dimension of single trace local
operators composed of two types of scalar fields in N=4 super Yang-Mills and
the energy of their dual semiclassical string states in AdS(5) X S(5). The
anomalous dimensions can be computed using a set of Bethe equations, which for
``long'' operators reduces to a Riemann-Hilbert problem. We develop a unified
approach to the long wavelength Bethe equations, the classical ferromagnet and
the classical string solutions in the SU(2) sector and present a general
solution, governed by complex curves endowed with meromorphic differentials
with integer periods. Using this solution we compute the anomalous dimensions
of these long operators up to two loops and demonstrate that they agree with
string-theory predictions.Comment: 49 pages, 5 figures, LaTeX; v2: complete proof of the two-loop
equivalence between the sigma model and the gauge theory is added. References
added; v4,v5,v6: misprints correcte
Classical/quantum integrability in non-compact sector of AdS/CFT
We discuss non-compact SL(2,R) sectors in N=4 SYM and in AdS string theory
and compare their integrable structures. We formulate and solve the
Riemann-Hilbert problem for the finite gap solutions of the classical sigma
model and show that at one loop it is identical to the classical limit of Bethe
equations of the spin (-1/2) chain for the dilatation operator of SYM.Comment: 27 pages, 1 figure; v2: unphysical windings around the time direction
eliminated; v3: dicsussion of finite-size corrections remove
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