[en] Automatic system for measurements and preliminary processing of film information from bubble chambers on the basis of the M-6000 microcomputer is described. The structure of the processing system is presented

[en] On the basis of processing the photographs taken from the 1 m propan-freon bubble chamber (Laboratory of Nuclear Problems, JINR irradiated with approximately 5 GeV/c π^--mesons on the JIR synchrophasotron, there are measured cross sections and investigated some characteristics of incherent reactions π^-A→ π^-πN ^-A' (on carbon nucleus and propan-freon muxture nuclei) and π^-A → π^- rho deg A' (on propan-freon mixture nuclei), which satisfy a kinematics of single-nucleon reactions. From the comparison with nucleon data, the cross sections of interaction of non-resonant dimeson systems (π^-π^-) and (π^-rho deg) with nucleon are estimated. A conclusion is made that mesons with momenta up to some GeV/c are formed inside nucleus

[en] In the π^-C-interactions at 5 GeV/c accompanied with the production of positively charged and neutral particles, topological cross sections, angular and momentum distributions and mean multiplicities of secondaries are measured. Full topologic cross section of processes of pion-carbon interactions without formation of negative particles makes up (7.28+-0.41)mb. It is shown that the cascade-evaporation model poorly describes distributions over cross sections and multiplicities of fast positively charged particles and of π⁰-mesons

[en] A detailed analysis of the inclusive production of the vector mesons Φ, K^*,0(892), K-bar^*0(892), ρ^+,0, ω and the tensor mesons K^*0₂(1430) and f₂(1270) in K⁺p interactions at 250 GeV/c is presented. The data are compared with results at lower energies and with predictions of various quark-parton models. The production of ρ⁰, K^*0(892) and K-bar^*0(892) increases at the same rate as a function of energy, is concentrated in the central region and is not reproduced by the models. Production of the tensor mesons f₂(1270) and K₂^*0(1430) is suppressed relative to ρ⁰ and K^*0(892) by a factor of about 3. 33 refs.; 17 figs.; 9 tabs

[en] The A dependence of charged-particle spectra in π⁺, K⁺, and p interactions with Al and Au targets at 250 GeV/c are presented and compared to predictions of the Quark-Gluon String Model (QGSM). It is shown that A dependence of invariant inclusive charged-particle spectra is very weak between Al and Au targets. The QGSM shows a larger difference between fast-particle spectra both for Al and Au targets and different beam particles. The QGSM prediction for the leading-particle spectrum over an energy range from 250 GeV to 10 TeV in pAu(Pb) reactions is in a reasonable agreement with the results of NA22 data and with a cosmic-ray experiment

[en] Using JINR 1m propane bubble chamber pictures, the π^-12C total cross section at 4.9 GEV/c has been measured to be sigmasub(c)sup(T)=(270 +- 20) mb. The estimate of the π^-12C absorption cross section makes sigmasub(c)sup(a)=(233 +- 22) mb

[en] Cross-sections are obtained for coherent interactions of π⁺ and K⁺-mesons with Al and Au nuclei at 250 GeV/c, leading to three, five and seven charged mesons. The total coherent cross-section is (4.3±0.5)% of the inelastic cross-section for each of the four meson-nucleus interactions. In 85% of the coherent events, the charged meson production is accompanied by neutral mesons. Effective mass distributions are presented for coherently produced particles, including charged mesons and photons, carrying total measured energy of more than 85% of the initial energy. Charged particle and γ spectra are analysed. No charge asymmetry is observed within the coherently produced cluster. (orig.)

[en] Preliminary results of the investigation to study the double charge-exchange like processes in the π^-12C→m₁π⁺+m₂p+m₃γ+C' (1) reaction (where m₁, m₂, m₃ are numbers of identified pions plus, protons and photons, respectively; c' is an unidentified nucleus-residue and neutrons) are presented. The cross section of the reaction was measured at a propane bubble chamber at 5 GeV/c and proved to be 3.4+-0.4 mb. The cross section of the reaction without π⁰s production proved to be 1.25+-0.45 mb, and with the production of one or more π⁰s - 2.15+-0.50 mb. Average π⁰ multiplicity in the reaction (1) was 1.37+-0.11. The cross section of the ''elastic'' double charge-exchange processes (energetic π⁺ in the forward direction) was found to be 0.26+-0.07 mb

[en] The NA22 data on π^-π^- correlations are analyzed in terms of a number of two- and three-dimensional parametrizations (Gaussian space-time, Goldhaber, Bowler string-like, Bertsch hydrodynamical, Kopylov-Podgoretskii, etc.). Contrary to the results obtained for e⁺e^- and μp collisions, the Goldhaber parametrization, as well as string-like models, fail in describing the hadron-hadron data. Better fits are obtained in the framework of surface-emitting fireball-like models, both when including and excluding hydrodynamical expansion of nuclear matter. Our results indicate that pion radiation occurs at earlier stages of matter evolution than in nuclear collisions. (orig.)

[en] Bose-Einstein correlations up to fourth order are presented at √s 22 GeV. Genuine third-order correlations are observed. The experimental data are compared with predictions from a quantum statistical approach of radiation from a partially coherent source and with the FRITIOF model. (orig.)