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An equilibrium thermoelastic state of two plates connected by a thin layer is examined. The problem is reduced to a system of six second-order differential equations. Temperature deformations of a bimetallic plate clamped at one edge and free at the other are considered. In the case of zero thickness of the interaction layer, the law of change of the interface line and the distribution of stresses along this line are obtained. In a uniform state (pure bend), the curvature of the interface line becomes constant. For zero Poisson ratio, the temperature dependence of the curvature is obtained. [ABSTRACT FROM AUTHOR]

Based on experimental data on the combined loading of an infinite layer weakened by a circular hole in a brittle material, its critical state, determined by the energy criterion, is modeled. The failure criterion is related to the free energy flow through the interaction arc and the linear size. The proposed approach allows us to reflect the dependence of the critical external load on the radius of curvature. A procedure for determining the value of the linear size is proposed and implemented. Using known experimental results, an estimate of the introduced linear parameter for a layer of GVVS-16 gypsum was obtained. [ABSTRACT FROM AUTHOR]

This paper describes a study of deformation of an ideal elastoplastic adhesive layer of a sample in the form of an elastic double-cantilever beam. The integral values are determined for a number of adhesives with account for all diagonal stress tensor components in the layer. It is shown that the integral value is significantly affected by the plane problem type in the case where an elastic-plastic model of layer deformation is applied. As demonstrated in the study, compressive stresses may be present during normal fracture in the irreversible deformation region of the adhesive in a plane stressed state. [ABSTRACT FROM AUTHOR]

The state of pre-fracture of a thin adhesive layer of finite thickness in the vicinity of a crack-like defect is considered. It is proposed to take into account the hydrostatic pressure, which forms the volume deformation energy, in order to find the critical state. The critical value of the J-integral for the I+II loading mode is assumed to be dependent on the product of the volume strain energy and the layer thickness at the end face of the adhesive. The limiting value of the product of the volume energy and the layer thickness under loading in mode I, as well as the critical values of the J-integral for loading modes I and II, determine the value of the loosening parameter of a particular adhesive in the proposed failure criterion. [ABSTRACT FROM AUTHOR]

The effect of a hole radius in an elastic layer on a critical external load at the moment of the onset of fracture, determined by the energy criterion, is investigated. A free energy flow through an interaction arc is used as a fracture criterion to describe the dependence of a critical external load on a hole radius. The length of the interaction arc constructed in the vicinity of a free energy peak point is determined using a linear parameter. The introduced linear parameter for a polymethyl methacrylate layer is obtained using known experimental data. The maximum value of the linear parameter can be taken as a material constant. [ABSTRACT FROM AUTHOR]

This paper presents the results of measuring the parameters of scintillation cubes, which are elements of the active target of the upgraded near detector of the T2K experiment, with the scintillation of a polystyrene-based organic scintillator being excited by an ultraviolet LED. Most attention is paid to the study of light leaks through the side faces of the cubes. The measurement results show that an average value of the coefficient characterizing light leaks through one face of the cube is 0.026. The effect of heating scintillation cubes on the light collection from them and light leaks are studied. After keeping the cubes at a temperature of 60°C for 72 h, the light collection from the cubes and the light leaks remained at the same level. [ABSTRACT FROM AUTHOR]

New position-sensitive experimental results have been obtained using the Dividing Plates method to detect the displacement of a single-mode laser beam spot of various diameters. Measurements show that with this method it is possible to attain sensitivities down to 0.18 µm–1 for a laser beam spot diameter of 8.8 µm displaced over 2.4 µm diameter zone, defined as the area where measurements non-linearities are within 1%. The achievable measurement accuracy is limited by ADC noise and corresponds to ±0.030 nm. Application of the Dividing Plates method for position-sensitive measurements allows to build a compact version of the Precision Laser Inclinometer, the Compact PLI, with reduced overall dimensions of 20 × 20 × 20 cm3 and weight of approximatively 10 kg. [ABSTRACT FROM AUTHOR]

A comparison of two models of the behavior of the material of a thin adhesive layer and their influence on the value of the J-integral for a specific experimental sample with specified mechanical and geometric properties is considered. A linearly elastic model of behavior and a model that takes into account the zone of weakened bonds with a finite linear distribution of the stress field are studied. The value of the J-integral is determined via the product of the specific work of the stresses and the thickness of the adhesive layer in the area of adhesive bond breaking. It is assumed that the thickness of the adhesive is finite and small compared to the thickness of the cantilever of the DCB sample. The finiteness of the layer thickness makes it possible to determine its deformations at relatively small thicknesses and to find the corresponding energy product. The distribution of stresses in the model with a zone of weakened bonds, determined by the ultimate strength and ductility of the adhesive, introduces the determining value of the J-integral. For an adhesive with pronounced plastic properties, the result of calculating the J-integral, taking into account the finiteness of the stress state, gives a result close to the experiment in comparison with the elastic model. [ABSTRACT FROM AUTHOR]

On the basis of the general variational formulation of the problem of the deformation of two bodies connected by a thin layer, a system of differential equations of equilibrium of the double-cantilever beam is obtained, taking into account the shear deformations of the cantilevers, both in the interface section and in the free section, taking into account also the elastoplastic properties of the layer. In this work, we use the connection representation of the J-integral in terms of the energy product and the energy product of dissipation. For purely elastic deformation, on the basis of the analytical solution of the system, an expression is obtained for the stress state of an extremely thin layer connecting the cantilevers, which is dependent on the material properties of both the layer and the cantilevers. The obtained expression for the elastic energy flux is compared with the known ones. The energy product at the top of the layer is found, the value of which depends only on the material properties of the consoles. With the elastoplastic behavior of the layer, the energy product of dissipation was found, which turned out to be dependent on the yield stress of the adhesive. The energy product in this case is proportional to the layer thickness. For adhesives with pronounced plastic properties, taking into account the dissipative mechanism of energy release leads to fundamental differences in the J-integral in comparison with the elastic calculation. The dependences of the DCB sample compliance with subcritical growth of the plastic deformation region in the adhesive are plotted. [ABSTRACT FROM AUTHOR]

The neutrons for science facility (NFS), the first operational experimental area of the new GANIL/SPIRAL-2 facility, received its first beams in December 2019. Proton-induced reaction cross-sections as well as neutron beam characteristics were measured during the first commissioning phases. The first results, showing the features of the facility, are presented here and compared with previously published data. The physics cases and the first accepted experiments are presented as well. [ABSTRACT FROM AUTHOR]

The differential cross sections of the charge exchange reaction d p → (p p) n has been measured at 1.75 GeV/c per nucleon for small transferred momenta using the one arm magnetic spectrometer STRELA at the Nuclotron accelerator in JINR Dubna. The ratio of the differential cross section of the charge exchange reaction d p → (p p) n to that of the n p → p n elementary process is discussed in order to estimate the spin-dependent part of the n p → p n charge exchange amplitude. The n p → p n amplitude turned out to be predominantly spin-dependent. [ABSTRACT FROM AUTHOR]

The stress-strain state of a thin adhesion layer in a layered composite is investigated under shear loading taking into account its possible elastoplastic deformation. The layer thickness is treated as a linear parameter. Analyzed is the analytical solution obtained on the basis of a simplified formulation of the problem in differential form. For small layer thicknesses, a generalized criterion for the transition to the state of plasticity associated with a linear parameter is proposed. [ABSTRACT FROM AUTHOR]

Fracture of the adhesive layer (AL) of finite thickness with elastoplastic properties in a layered composite is considered in this article. The expression of the J C -integral is obtained as the sum of values of the products of the layer thickness and the increments of the specific free energy and specific dissipation. Based on the variational formulation, a solution to the model problem of shear action on a thin elastoplastic layer is obtained. From the analysis of the solution obtained, it follows that in the case of a layer degenerating into a mathematical section, the main contribution to the representation of the J C -integral is made by the term responsible for the energy dissipation, and the energy product tends to zero. In this case, it is not pure dissipation that is considered, this is the product of specific dissipation and layer thickness. The expression of the J C -integral is obtained in terms of the quantities measured in a possible experiment. [ABSTRACT FROM AUTHOR]

The analyzing powers for proton elastic scattering ( p A → p X ) and neutron charge exchange ( n A → p X ) reactions on nuclei have been measured on C, CH, C H 2 and Cu targets at incident neutron momenta 3.0–4.2 GeV/c by detecting one charged particle in forward direction. The polarized neutron measurements are the first of their kind. The experiment was performed using the Nuclotron accelerator in JINR Dubna, where polarized neutrons and protons were obtained from break-up of a polarized deuteron beam which has a maximum momentum of 13 GeV/c. The polarimeter ALPOM2 was used to obtain the analyzing power dependence on the transverse momentum of the final-state nucleon. These data have been used to estimate the figure of merit of a proposed experiment at Jefferson Laboratory to measure the recoiling neutron polarization in the quasi-elastic 2 H (e , e ′ n) reaction, which yields information on the charge and magnetic elastic form factors of the neutron. [ABSTRACT FROM AUTHOR]

Finite deformation of a panel under the influence of pressure is considered. The statement of the problem in displacements with equilibrium conditions represented via true stresses in Lagrangian coordinates is proposed. It is proven that the initial equations are satisfied when the panel is uniformly curved during deformation. The use of the previously proposed defining relation makes it possible to determine a differential relationship of the laws of pressure and curvature with time at an arbitrary strain rate. Ideally plastic and superplastic deformations are considered. The dependences of pressure on the curvature and strain time are obtained at which superplasticity occurs. It is revealed that, in this case, the range of stable changes in the curvature does not depend on the strain rate, and the threshold stress does not affect the time it takes to reach a given curvature of the panel. [ABSTRACT FROM AUTHOR]

The decreasing of the relaxation time for recovery of the horizontality of the surface of thin layer of the liquid in the cuvette is a new observed phenomenon caused by the meniscus influence in case of the cuvette small inclination. It was experimentally established that the time of reconstruction of the surface of 4 mm thick liquid layer in the cuvette of ∅5 mm at 0.5 µrad of calibration inclining is 0.082 ± 0.006 s. In this case the relative deviation from the liquid surface planarity does not exceed 7%. The physics explanation of the phenomenon observed is proposed. The taking into account of the time duration of liquid surface horizontality reconstruction in the Precision Laser Inclinometer has resulted in the widening of Inclinometer's sensitivity range up to 12.3 ± 0.9 Hz. The data obtained could be used when seismoisolating of the research equipment. [ABSTRACT FROM AUTHOR]

In the Professional Precision Laser Inclinometer the noise origins were analyzed. The new efficient methodic of these noises taking into account was proposed and realized. The own (instrumental) noise 6 × 10–12 rad/Hz1/2 of the PPLI has been measured in the frequency range of [0.1 Hz; 1 Hz]. The minimal PPLI registered spectral density when analyzing of a daylong data was 2.4 × 10–11 rad/Hz1/2. [ABSTRACT FROM AUTHOR]

A model of a physical section that describes stress-strain states in elastic-plastic solids weakened by cracks is proposed. The problem of plane deformation and the stress state of a solid of an infinite size of an arbitrary geometry, weakened by a physical section, is solved. It comes down to a system of two variational equations with respect to displacement fields in the parts of the solid bordering the interaction layer. For a material whose properties are close to those of a D16T alloy, the linear parameter introduced into the crack model is estimated, and the critical conditions of solids with lateral cracks in the case of a normal detachment are determined. [ABSTRACT FROM AUTHOR]

The Hydrostatic Level System (HLS) data and the Precision Laser Inclinometer (PLI) instruments data have been comparatively analyzed in the event of surface angular oscillations induced by earthquakes. The comparative data analysis has shown an agreement on the arrival and stop time of earthquakes. The data have been analyzed within the instruments sensitivity ranges having an overlap in frequency intervals. [ABSTRACT FROM AUTHOR]

In this report a high accuracy method for an interferometric calibration of the Precision Laser Inclinometer (PLI) is proposed. The method is based on the simultaneous measurement of: (a) the PLI base calibration slope (angle), set by a piezoelectric positioner, via laser interferometry and (b) the PLI response signal. A calibration coefficient of 322.5 ± 1.9 μrad/V has been determined experimentally in an interval [4 × 10, 4 × 10] rad in which there is a linear dependence between the PLI-signal and the calibration angle. [ABSTRACT FROM AUTHOR]

The light collection of extruded scintillation strip samples with the help of WLS fibers placed in a longitudinal hole inside of the plates has been measured. The holes are filled with various liquid fillers. Measurements are performed under irradiation by cosmic muons. A method for pumping a liquid filler with a viscosity of more than 10 Pa s into the strip hole with a WLS fiber inside is devised and successfully tested. [ABSTRACT FROM AUTHOR]

A study of inelastic scattering and multi-particle transfer reactions was performed by alpha and He beams on a Be target at energy about 50 MeV. Angular distributions of the differential cross sections for the Be(α,α′)Be*, Be(α,He)Be, Be(α,t)B, Be(He,Li)Li and Be(He,Be)He reactions were measured. Experimental angular distributions of the differential cross sections for the ground state and a few low-lying states were analyzed in the framework of the optical model, coupled channels and distorted-wave Born approximation. The information on the cluster structure of the reaction products are obtained. An analysis of the obtained spectroscopic factors was performed. [ABSTRACT FROM AUTHOR]

Based on the model of a physical cut and a material layer on its continuation, elastic and elastoplastic problems of determining the stress-strain state inside and outside the layer in the case of loading of cut edges by an antisymmetric system of forces are posed and solved. The solution of the elastic problem is compared with the solution obtained within the framework of the Neuber-Novozhilov model. In contrast to the latter model, the proposed approach provides results consistent with experimental data on the process of formation of fracture regions. Based on the analysis of the discrete solution of the problem, regions of plastic deformation and regions of possible fracture are found. [ABSTRACT FROM AUTHOR]

The Precision Laser Inclinometer was tested at thermo-stabilized conditions and the ground angular stability of 1 μrad (observation during 24 h) and 7nrad (observation during 60 min) was measured. [ABSTRACT FROM AUTHOR]

The LYSO crystals of dimensions 30 × 30 × 130 mm and 10 × 10 × 10 mm are tested with different gamma sources. Energy resolutions and linearity of the energy responses in the energy range 511-1333 keV are measured. It is found that crystals have good linearity of the energy response in the entire tested energy range. Longitudinal light response non-uniformity of the long crystal is found to be less than 3.2% within the 30-120 mm range along the crystal axis. [ABSTRACT FROM AUTHOR]

The results of a comparative analysis of channels involving the inclusive production of deuterons and tritons in O p collisions at a projectile momentum of 3.25 GeV/ c per nucleon are presented. The mechanisms governing proton, deuteron, and triton production in the fragmentation of oxygen nuclei are found to be independent. It is shown that the observed proton-multiplicity correlations are associated predominantly with the character of the primary event of a proton-nucleon collision in O p interactions. It is found that, in reactions involving triton production, the contributions of processes leading to an increase in the mean proton multiplicity ( n → p + π and np → pn) and processes leading to its decrease ( p → n + π) compensate each other. [ABSTRACT FROM AUTHOR]

We propose a classification of individual nanoparticles on the basis of the form of the surface and the internal architectural packing for investigations carried out with the help of transmission electron microscopy. The investigated samples contain individual nanoparticles of seven kinds in different ratios: rounded, tubular, fibrous, fi lm, "veil," "active" particles and "particles with regular geometric contours." The classification was made on the basis of an analysis of the results of investigations of the surfaces and internal architectural packing of carbon particles obtained in different physiochemical processes (carbonization, carburizing, arc discharge, mechanochemical treatment, plasma chemistry, and in carbon-containing fl ames). For the source materials, we used waste of farming products and widely distributed mineral raw materials. [ABSTRACT FROM AUTHOR]

For the studies and calibration of optoelectronic components of the high-precision laser based metrology systems the large volume (50 m) thermoisolated lab based on seismic isolated concrete block is created. The inside lab volume temperature stabilization for the daily observation at 16.5°C is ±0.05°C with ±0.015°C temperature difference between maximal space separated points. This work was initiated by the needs of high-precision alignment of accelerator components of the CLIC, ILC-type colliders. [ABSTRACT FROM AUTHOR]

The next generation of linear colliders is very demanding concerning the alignment tolerances of their components. For the CLIC project, the reference axis of the components will have to be pre-aligned within 10 μm at 1 sigma with respect to a straight line in a sliding window of 200 m. A solution based on stretched wires with wire positioning sensors has been proposed in order to fulfill the alignment requirements in the Conceptual Design Report of the project. This solution has some drawbacks and laser based alternative solutions are under study in order to validate the wire solution and possibly replace it. A new proposal is introduced in this paper, using a laser beam over 150 m as a straight alignment reference, with the objective of having an uncertainty in the determination of its straightness within 10 μm. Sensors coupled to the components to be aligned, would provide after calibration the horizontal and vertical offsets with respect to the laser beam, within a few micrometers, in their coordinate system. The method is based on the laser beam space stabilization effect when a beam propagates in atmospheric air inside a pipe with standing acoustic wave. The principal schemes of corresponding optoelectronics devices and temperature stabilization solutions are also proposed, making probable the extension of the laser fiducial line up to a 500 m length. [ABSTRACT FROM AUTHOR]

The results obtained by studying the production of six-nucleon systems and nuclei that is accompanied by the yield of charged pions in O p collisions at a momentum of 3.25 GeV/ c per nucleon are presented. It is shown that the correlation of the yield of mirror H (He) nuclei with the production of π ( π) mesons is due to the charge-exchange process involving an oxygen-nucleus proton (neutron) knocked out predominantly from an alpha-particle cluster. [ABSTRACT FROM AUTHOR]

A precision method for measuring of ultrahigh unloaded Q factors of superconducting cavities is proposed which is based on the excitation of oscillation in the cavity by electron beam. In this measuring, the cavity is not connected to any external microwave circuit; its unloaded Q factor is determined from the loss of electron-beam power, which can be measured with high accuracy. [ABSTRACT FROM AUTHOR]

The STRELA experimental setup designed for studying charge-exchange processes in deuteron-proton collisions at energies above 1 GeV is described. The setup is a one-arm magnetic spectrometer the main elements of which are drift chambers. The setup has been tested by irradiation in a deuteron beam with a momentum of 3.5 GeV/ c at the Nuclotron accelerator complex (Laboratory of High Energy Physics, Joint Institute for Nuclear Research (JINR)). Algorithms for track searching and reconstruction in drift chambers have been developed and tested using real events. The attained spatial resolution of the chambers is in the range of 90-120 μm, which is sufficient for studying the process we are interested in. [ABSTRACT FROM AUTHOR]

A model describing the stress-strain state in the neighborhood of a physical cut with an arbitrary distribution of external load along its faces is presented. The stress-strain state of a material layer bounded by the continuations of the cut faces is considered. The interaction between the layer and the external half-planes leads to a closed system of integrodifferential equations for the mean stress components in the layer, which splits into two equations for the mean normal stresses and an equation for the mean shear stress. Numerical solutions of the system for the cases of symmetric and antisymmetric loading of the faces by concentrated forces are given. Conditions for the transition of the tip region of the cut to the state of plasticity and fracture are considered. [ABSTRACT FROM AUTHOR]

The problem of determining the stress-strain state of an elastic plane with a physical cut loaded by an antisymmetric system of forces is posed and solved under the condition that the tangential stresses are homogeneous across the thickness of the layer continuing the cut. [ABSTRACT FROM AUTHOR]

New experimental data on the correlations of the yields of He and H nuclei in semi-inclusive reactions involving by the production of He and H mirror nuclei in O p collisions at a momentum of 3.25 GeV/ c per nucleon are presented. The mean multiplicities of protons and neutrons appearing as fragments are found to be independent of the number of associated deuterons, this indicating that a considerable part of these fragments originate from the breakup of the alpha-particle clusters forming the oxygen nucleus. [ABSTRACT FROM AUTHOR]

New experimental data on the dependence of the mean multiplicities and kinematical features of He nuclei produced in O p collisions at a momentum of 3.25 GeV/ c per nucleon on the degree of excitation of the fragmenting nucleus are presented. Strong correlations between the multiplicities of negatively charged pions and He nuclei are found. [ABSTRACT FROM AUTHOR]

Computations of the accelerator section of the International Linear Collider (ILC), which consists of superconducting niobium cavities, are performed for conditions of the maximum energy transfer to electrons that travel along the cavity axis. A mathematical model and software packages are created for the computation of the electric characteristics and profile of a single-cell cavity. A computer-based synthesis of the cavity shape that yields the required electric characteristics is performed. The promising design variants of a single-cell cavity, with which a quality factor of 10 is provided at a working frequency of 1.3 GHz, are found to optimize the construction and manufacture of a single-cell cavity. The electric characteristics of a chain of single-cell cavities are computed. [ABSTRACT FROM AUTHOR]

New experimental data on the dependences of the mean multiplicities and kinematical characteristics of deuterons produced in Op collisions at a momentum of 3.25 GeV/ c per nucleon on the degree of excitation of the fragmenting nucleus are presented. These experimental data are compared with the predictions of the cascade-fragmentation-evaporation model. [ABSTRACT FROM AUTHOR]

Results of a comparative analysis of processes leading to the production of mirror nuclei Li and Be in O p collisions at a momentum of 3.25 GeV/ c per nucleon are presented. A comparison of associated multiplicities of accompanying particles is performed. The first results on the mean multiplicity of neutrons appearing as fragments are described. [ABSTRACT FROM AUTHOR]

Scintillation counters are an important part of the muon detection system at CDF II (FNAL, United States). Permanently controlling and maintaining the high performance of these detectors are essential for obtaining high-quality experimental data. The first version of the control system of scintillation counters created in 2001 was completely upgraded by us due to increased requirements for the control systems of subsystems at CDF in connection with the growth of Tevatron luminosity, the introduction of new devices, and the experience of operation. [ABSTRACT FROM AUTHOR]

We developed a simple algorithm allowing automated generation of map slices and cross sections from discrete values of geological and geophysical parameters described by 3D data sets. The data input and output were handled in the standard formats of Word, DOS, and the Surfer 8 package, which make it possible to be widely used by small scientific and technical teams in the processing of geological information and the interpretation of local GISs. The practical implementation of the proposed algorithm is exemplified by the study of the density properties in the Earth’s crust and upper mantle of Transbaikalia and Sikhote-Alin. [ABSTRACT FROM AUTHOR]

We consider models of strain and separation processes of rigid bodies, which are based on the use of the well-known scheme of mathematical cut [1, 2] and the concept of interaction layer developed in [3, 4]. We obtain a thermomechanical condition for the separation of a deformable body in the framework of physical and mathematical cut models. This condition allows us to obtain the general expression for the surface energy as the product of the interaction layer thickness by the critical free energy, which holds for the reversible (elastic) and irreversibly deformable materials. When using the mathematical cut model in an elastic body, the expressions of the surface energy is reduced to the classical Irwin-Orowan representation [1, 5]. On the basis of semidiscrete and discrete models of the interaction layer, we state the problem of determining the subcritical state of a plane loaded by a physical cut under symmetric loading by lumped forces and an end load. We compare the results obtained by the discrete model with the asymptotic solution obtained in [6] in a specific case. It follows from the proposed fracture criterion that an increase in the end loadmay result in the critical state attained at a certain distance from the end surface. This effect was observed in the experiment described in the monograph [7]. [ABSTRACT FROM AUTHOR]

The study of different modifications for the procedure of determining the reconstructed mass based on the kinematic fit for dilepton events to improve the precision of the top quark mass measurement using the template method is described. It is demonstrated that accounting for the top quark decay width from its mass reduces the statistical measurement error by approximately 20%. The possibility of using transfer functions for a detailed description of the connection between the experimentally measured energy characteristics of b jets and the momenta of b quarks that produced these jets is considered. The capabilities of the modified method as used for the “lepton plus track” sample of the CDF experiment are evaluated. [ABSTRACT FROM AUTHOR]

A problem of the development of a plastic zone in the vicinity of a physical cut in the plain strain and stress states is posed and solved on the basis of a discrete deformation model under the assumption of an ideal elastoplastic medium. The Tresca yield condition and the ultimate plasticity condition are used in studying the plane stress state. The dependence of the plastic zone length on the external load is compared with a similar dependence obtained on the basis of the Leonov-Panasyuk-Dugdale model. In contrast to the Leonov-Panasyuk-Dugdale model, the distributions of stresses and lengths of plastic zones in the plane strain and stress states are found to be substantially different if elastic compressibility and compressive-tensile stresses along the cut direction are taken into account. [ABSTRACT FROM AUTHOR]

The problem of the beginning of motion of a cut in a plane under symmetric external loading is considered. The material lying on the cut continuation forms a layer (interaction layer). A transition to a plastic state within the layer is assumed to be possible. The behavior of the layer is described by an ideally elastoplastic model, and the plane outside the layer is assumed to be linearly elastic. A system of boundary integral equations for determining the stress-strain state is derived. Based on this system, a discrete model of separation of the layer material is constructed under the assumption of a constant stress-strain state in the element of the interaction layer. The distribution of stresses in the pre-fracture zone is determined. [ABSTRACT FROM AUTHOR]

The differential cross section and deuteron analysing powers of the $$ \vec d $$ p → { pp} n charge-exchange reaction have been measured with the ANKE spectrometer at the COSY storage ring. Using a deuteron beam of energy 1170MeV, data were obtained for small momentum transfers to a { pp} system with low excitation energy. A good quantitative understanding of all the measured observables is provided by the impulse approximation using known neutron-proton amplitudes. The proof of principle achieved here for the method suggests that measurements at higher energies will provide useful information in regions where the existing np database is far less reliable. [ABSTRACT FROM AUTHOR]

The results of a comparative analysis of the multiplicities of singly and doubly charged accompanying particles in the channels involving the production of six- and seven-nucleon systems in 16O p collisions at a momentum of 3.25 GeV/ c per nucleon are reported. Cross sections for the yield of multinucleon systems and mean multiplicities of accompanying particles are found. The experimental data are compared with the predictions of the cascade—fragmentation—evaporation model. [ABSTRACT FROM AUTHOR]

A problem of the beginning of motion of a finite-width cut in a linearly elastic plane under the action of symmetric external loading is formulated. The material on the way of cut propagation forms a layer (interaction layer). The stress-strain state of the material is postulated to be homogeneous across this layer. A system of integral boundary equations is obtained for determining the stress-strain state. Based on this system of equations, a discrete model of separation of the layer material is constructed under the assumption of a constant stress-strain state in an element of the interaction layer. The stress distribution in the pre-fracture zone is determined. [ABSTRACT FROM AUTHOR]

This paper considers a model for the opening-mode fracture separation process based on the introduction of an interaction layer. This layer is defined as the region of localization of the fracture process. The stress-strain state of the layer material is uniform in the cross section of the layer. A study is made of the deformation of a double-cantilever beam weakened by a notch whose width is equal to the thickness of the interaction layer. The problem is solved in a linearly geometrical approximation. The thickness of the interaction layer is estimated, and a method for solving the formulated problem is proposed. [ABSTRACT FROM AUTHOR]