The necessity of describing three-nucleon and three-quark systems have led to a constant interest in the problem of three particles. The question of including relativistic effects appeared together ...with the consideration of the decay amplitude in the framework of the dispersion technique. The relativistic dispersion description of amplitudes always takes into account processes connected with the investigated reaction by the unitarity condition or by virtual transitions; in the case of three-particle processes they are, as a rule, those where other many-particle states and resonances are produced. The description of these interconnected reactions and ways of handling them is the main subject of the book.Contents:IntroductionElements of Dispersion Relation Technique for Two-Body Scattering ReactionsSpectral Integral Equation for the Decay of a Spinless ParticleNon-relativistic Three-Body AmplitudePropagators of Spin Particles and Relativistic Spectral Integral EquationsIsobar Model and Partial Wave Analysis. D-Matrix MethodReggeon-Exchange TechniqueSearching for the Quark-Diquark Systematics of BaryonsConclusionReadership: Grudate students and researchers in high energy and particle physics.
Data on the reaction γp→K^{+}Λ from the CLAS experiments are used to derive the leading multipoles, E_{0+}, M_{1-}, E_{1+}, and M_{1+}, from the production threshold to 2180 MeV in 24 slices of the ...invariant mass. The four multipoles are determined without any constraints. The multipoles are fitted using a multichannel L+P model that allows us to search for singularities and to extract the positions of poles on the complex energy plane in an almost model-independent method. The multipoles are also used as additional constraints in an energy-dependent analysis of a large body of pion and photoinduced reactions within the Bonn-Gatchina partial wave analysis. The study confirms the existence of poles due to nucleon resonances with spin parity J^{P}=1/2^{-}, 1/2^{+}, and 3/2^{+} in the region at about 1.9 GeV.
In his book, Vyacheslav Nikonov shows the origins of the modern world and traces the chronologies and histories of peoples and countries. Nikonov discusses the main centers of influence and forces ...that shape the world in which we live. The world demonstrates a variety of development models shaped by the national, regional, historical, religious and other aspects of each country. The center of gravity of world development is shifting from West to East, from North to South, from developed economies to ??developing ones. Thirty years ago, Western countries accounted for 80% of the world economy; now it is less than half. Asia, already home to most of humanity, will become a global leader in the coming decades. What does this mean? What will the world be like and what place will Russia take in it? Will American hegemony continue? Will China become a superpower? Will Europe become a museum for tourists from other continents? History has resumed its course and the world is rushing towards an unstoppable diversity. Published with the support of the Institute for Literary Translation, Russia.
Properties of nucleon and
Δ
resonances are derived from a multichannel partial wave analysis of pion and photo-induced reactions off protons. This paper summarizes the latest results on masses, ...widths, and decay properties of nucleon and
Δ
resonances.
Hyperon II: Properties of excited hyperons Sarantsev, A. V.; Matveev, M.; Nikonov, V. A. ...
The European physical journal. A, Hadrons and nuclei,
10/2019, Letnik:
55, Številka:
10
Journal Article
Recenzirano
Odprti dostop
.
We report properties of
Λ
and
Σ
hyperon resonances formed in
K
-
induced reactions. Special emphasis is laid on the analysis of the three-body final states
2
π
0
Λ
and
2
π
0
Σ
and of the ...quasi-two-body final states
π
Λ
(
1520
)
,
K
¯
Δ
(
1232
)
,
π
Σ
(
1385
)
,
K
¯
*
N
, and
ω
Λ
. We give pole positions of
Λ
and
Σ
hyperon resonances and transition residues from the
K
-
p
initial to various final states as well as Breit-Wigner masses and widths and decay branching ratios. Twenty resonances and “bumps” reported in the Review of Particle Physics are not required in our fits, evidence for five new resonances is reported. The observed mass spectrum is compared to the spectrum calculated in the Bonn quark model. Three spin doublets, six
Λ
hyperons, are tentatively assigned to the
SU
(3) singlet system.
Proton-η′ interactions at threshold Anisovich, A.V.; Burkert, V.; Dugger, M. ...
Physics letters. B,
10/2018, Letnik:
785, Številka:
C
Journal Article
Recenzirano
Odprti dostop
Recent data on photoproduction of η′ mesons off protons have been included in the data base for the Bonn–Gatchina partial wave analysis. The real and imaginary parts of the S-wave η′p→η′p scattering ...amplitude in the threshold region were fit to yield the η′p scattering length and the interaction range. This new analysis found |aη′p|=(0.403±0.015±0.060) fm and a phase ϕ=(87±2)∘, while the range parameter is not well-constrained. The striking behavior of the GRAAL data on the beam asymmetry in the threshold region suggests that a narrow proton-η′ resonance might exist. However, the scattering length was found to be relatively insensitive to the possible existence of this narrow resonance.
Search for the tensor glueball Klempt, E.; Nikonov, K.V.; Sarantsev, A.V. ...
Physics letters. B,
07/2022, Letnik:
830
Journal Article
Recenzirano
Odprti dostop
The tensor glueball is searched for in BESIII data on radiative J/ψ decays into π0π0 and KsKs. The ππ invariant mass distribution exhibits an enhancement that can be described by a pole at ...(2210±60)−i(180±60)MeV or by three of ϕϕ resonances suggested a long time ago to be the trace of one, two or three glueballs. We speculate that several high-mass tensor mesons might have qq¯ and glueball components.
•The chemical interaction between Pr1−xSrxFe1−yCoyO3 and YSZ intensifies with increasing x and y.•The Pr1−xSrxFe0.8Co0.2O3 compositions possess minimum thermal expansion at Sr content of x = 0.3.•The ...conductivity of Pr1−xSrxFe0.8Co0.2O3 increases with increasing Sr content.•The polarization resistance of Pr1−xSrxFe1−yCoyO3 in contact with GDC decreases with increasing x.
The new cathode materials Pr1−xSrxFe1−yCoyO3 (0 ≤ x ≤ 0.4; y = 0.2, 0.5) for SOFC have been studied. The materials were synthesized by the self-propagating high-temperature synthesis method. It was shown that the chemical activity of Pr1−xSrxFe1−yCoyO3 (PSFC) with respect to Zr0.84Y0.16O2−δ (YSZ) electrolyte increases with increasing concentration of Sr and Co, whereas the interaction with Ce0.73Gd0.27O2−δ (GDC) electrolyte was not found. The thermal expansion of praseodymium ferro-cobaltite nonlinearly depends on the Sr content with a minimum at x = 0.3. The conductivity of the investigated materials increases with an increase of Sr and Co content. The cathode materials in contact with YSZ have a high polarization resistance (a few Ω cm2 at 850 °C) due to their chemical interaction. Replacement of YSZ electrolyte with GDC results in the reduction of the polarization resistance by an order of magnitude. The Pr0.6Sr0.4Fe0.8Co0.2O3 in contact with GDC has the lowest polarization resistance of 0.05 Ω cm2 at 850 °С.
Abstract
Used electron-beam additive manufacture with two wire filaments simultaneously produced composite 321SS/CuA19Mn2 with 50:50 components ratio. Investigated of microstructure and mechanical ...properties of composite 321SS/CuA19Mn2 and compared with properties of stainless steel with aluminum bronze produced by electron beam additive manufacture. It was found that the formation of the composite 321SS/CuA19Mn2 leads suppresses of the residual β’-phase: diffusion of elements initiates phase transition from γ-Fe to α-Fe and leads to formed nanoparticles of κ
iv
-phase in solid solution of α-Cu. Mechanical tensile tests and microhardness were showed composite 321SS/CuA19Mn2 have highest microhardness (∼3280 GPa) and highest tensile strength (830 MPa) as compared with steel and bronze produced by additive manufacture.
Display omitted
•Acoustic emission response to vibration in cutting has been studied.•Spectral AE characteristics were found being sensitive to vibration loading.•Median frequency shows a drop in ...chatter mode.•Power spectrum shifts to low frequency range.•Potential energy grows with the vibration amplitude.
Acoustic emission (AE) study of steady and chatter mode peakless tool turning has been carried out in order to reveal an acoustic emission response to the workpiece chatter during fine turning. Molecular dynamics simulation of acoustic emission response to chatter was used to find out fundamental system characteristics. Experimental dependencies of AE signal amplitude, median frequency and power spectrum have been obtained and compared to those obtained from the molecular dynamics (MD) simulation. Both experimental and MD simulated AE signal spectral characteristics proved to be sensitive to chatter mode vibrations. Median frequency showed a drop in chatter mode cutting as well as power spectrum shifted to the low frequency range. Such a relationship has been attributed to the growing level of the system potential energy.
PDF
