[en] The Einstein-Maxwell theory, with sources, but without current terms in the energy-momentum tensor, is shown to admit a particle-like solution. The solution has a timelike Killing vector as one of its symmetries; this Killing vector is not hypersurface orthogonal, so that the metric contains off-diagonal terms which cannot be removed by coordinate transformations. A second Killing vector, akin to a rotation about the z-axis, is also admitted, so that the putative particle appears to have just sufficient structure to represent a classical charged particle with spin. It is shown that the Einstein-Maxwell theory, with the type of sources and symmetries discussed, has a natural interpretation in terms of a Riemannian V₄ with a positive-definite metric. The geometry of this V₄ is simpler both conceptually and formally than the geometry of the Einstein-Maxwell theory, with or without sources, in an indefinite V₄

No abstract available

No abstract available

[en] A wire spark chamber with electrodynamical method of data pickup is described. The chamber is intended for investigation of multiparticle production and decay processes in wide-aperture magnetic spectrometers. The pulse sonic wave occurs during passing the current pulse along the signal wire from the spark discharge in the point of the sonic guide ad oining this wire. Excitation of this wave is the consequence of current interaction induced in the sonic guide by the current of spark break-down and the external magnetic field in which the chamber with the sonic guide is located. A piesotransducer fixing the coming of vibration spread by the sonic guide is placed at the end of the sonic gauide. The measured time between the pulse of spark discharge and pulse from piesotransducer contains data on the spark coordinate. Described are the designs of chambers, sonic guide and piesotransducer, presented are the flowsheets of preamplifier of piesotransducer signals, flowsheet of chamber supply, unit of start up of spark gaps of spark chambers and the flowsheet of a high- voltage pulse system of the spectrometer. The chamber with 590x1250 mm working region and 14 mm working gap has 1.0-1.5 μs time of memory, 0.25-0.35 mm accuracy of spark coordinate determination, 6 mm spatial resolution of two sparks, 0.8 efficiency of registration of six sparks

No abstract available

[en] A procedure for determining geometric reconstruction constants by the ITEP 6m magnetic spark spectrometer has been described. Geodesic measurements and the procedure described provide 0.3 m/m horizontal and 1.6 mm vertical accuracy of space reconstruction. The geodesic measurements are performed in two stages: chamber certification-measurement of point coordinates on mark filaments and soundguides in a system connected with two chamber marks (template system), conjunction to the spectrometer coordinate system-measurement of chamber mark coordinates in the working position of the chambers. The described method for determining constants is optimal, as it requires little time (approximately 2h) and can be used when necessary during each movement of the spectrometer chambers

[en] Amplitude analysis of the K_S⁰K_S⁰ system is performed using a sample of 15,184 events of quasi-elastic K_S⁰-meson pair production by 40-GeV/c π^- mesons incident on carbon nuclei. Model-dependent analysis of the observed set of partial waves demonstrates their complex structure. In the S and D₀ waves, evidence for the existence of previously unknown states is obtained. In the S wave, a complex structure is revealed in the vicinity of the f₀(1400) resonance. To describe this structure, it is necessary to introduce two resonances with masses near 1370 and 1500 MeV that decay predominantly into K bar K. 13 refs., 12 figs., 4 tabs

[en] ΛLbar effective mass distributions of 2300 events from reaction π^-p → ΛLbarn at 40 GeV measured at 6-meter spectrometer ITEP are presented. Bumps near 2.3, 2.5 and 2.8 GeV/c² are clearly seen. Singlet state dominates at 2.3 GeV/c², while state at 2.8 GeV/c² is mainly triplet

No abstract available

[en] Results of studying the ΛΛ-bar system obtained from reaction π^-p → ΛΛ-bar n at π^- mesons energy 40 GeV are provided. The experimental material (∼ 2300 events) was obtained in the 6 m ITEP spectrometer in the U-70 accelerator (IHEP) beam. Essential difference in spectra of effective masses during sampling was observed emphasizing either singlet or triplet of the ΛΛ-bar system. The data suggest existence of the ΛΛ-bar system resonance states in the range of masses 2.3, 2.5 and 2.8 GeV