[en] The invention is aimed at determination of differential distribution of particle density in a beam along its cross section while operating with high-intensity beams ( >100mA) . According to the proposed method the products of beam interaction with substance atoms, renewed while measuring are recorded with the help of detectors, placed outside the beam. The renewed substance is passed through the beam in the form of a stable flat jet and the density of beam interaction products with the jet atoms is measured. The coordinates of the points of product appearance in the jet is also determined, and the beam particle density is judged by them

[en] Problems of physics and chemistry of muon atoms: muon beam production, muon moderation, process of atomic capture, processes determining the structure of meso-X radiation and effect of different factors on it, muon depolarization in a mesoatomic cascade and after cascade completion, formation of radiolysis zone near the region of muon atom formation, chemical reactions of muon atoms, slow relaxation of a muon spin, are presented

[en] Depolarization of negative muons in Esub(m)Osub(n) oxides mainly of the elements of the 4 and 5 periods are studied with the aim of checking to what extent chemical properties of an element E define the occurence of chemical reactions involving oxygen mesic atoms. The muon relative polarization a/ac (in reference to graphite) was determined by means of the muon spin precession method in a weak transverse magnetic field. The experiment was carried out at room temperature and for a number of oxides at the liquid nitrogen temperature. The results obtained are compared to the hydroxide data. An increase of the residual polarization with increasing atomic number from the beginning to the end of the period is observed for the oxides of the fifth period. For the oxides of the fourth period a change in a/ac for different oxides is larger as compared to hydroxides. As for hydroxides, an increase in a/ac with decreasing the ionicity (i) of the E-O bond is observed for all oxides excluding transition element oxides of the 4 period. This points to the resemblance of chemical reactions of mesic nitrogen in the both types of compounds

[en] The main features of the Au-Yang and Cohen model are analysed which accounts for the dependence of μ^- atomic capture on atomic number Z in oxides. It is noted that the use of the Pauling formula to calculate the charge transfer parameter Z is not rightful. The other assumption of the model in question concerning the monotonous increase of the relative capture probability of muons by a cation in MgO as a function of Zsub(f) and its use as a normalizing curve for other oxides were experimentally tested. For this purpose muon-capture data are considered in a number of compounds which are isoelectronic with respect to MgO. The analysis shows that an increase in the charge transfer parameter and effective cation charge when passing from WH₄⁺ and Na⁺ to Mg²⁺ leads to a decrease in the relative capture probability. The notion of the ionic and covalent charges of the chemical bonds of atoms oppositely influencing muonic capture is introduced to explain the observed regularities in μ^- capture in oxides and halogenides

[en] Studies were made to elucidate the relative capture probability of muons by hydrogen-containing fragments and substituent atoms in aliphatic chlorine-alkyls Csub(n)Hsub(2n+1)Cl. μ^--capture probabilities were determined from time spectra of μ^--e^--decay. To interpret the data obtained partial shell probabilities of μ^--e^--substitution proportional to the cross sections were introduced to describe atomic or fragmentive location of negative mesons. This allows one to separate out the contributions of the chemical bond and the atomic structure in muonic capture and in particular to establish the difference between the partial probabilities for valence and inner-shell electrons. The data indicate that the relative probabilities of μ^--e^--substitution of the valence and inner electrons adiabatically change with chain elongation n and comes to plateau at n approximately equal to 4. At n (>=) 4 the probability for inner electrons is two times smaller than that for valence electrons. This difference may be explained by both the shielding effect and the difference in binding energy for inner and valence electrons

[en] For the first time the possibility of using a 2/3π√2 sector double-focusing magnet spectrometer to produce beams of pions- and polarized muons of both signs in the energy range 10³-10⁷ eV is demonstrated. The muon channel of the phasotron of the Laboratory of Nuclear Problems, JINR, is used as an intermediate device. Mesons from the channel lose part of their energy in an absorber, whose surface can be considered as a source of particles with the energy spread from zero to a few tens of MeV. The magnetic spectrometer separates meson beams of a necessary energy from the source

[en] Relative (with respect to graphite) asymmetry coefficients a/asub(c) in angular distribution of μ^- → e^- -decay electrons in water have been measured in the wide temperature range (from 4 K to a room temperature) by the muon spin precession method in a weak transverse magnetic field with better precision. The mesic atom chemical reaction rate in water has been obtained on the base of temperature dependence of residual polarization of negative muons: lambda₀=(1.9+-0.7)x10¹⁰ c^-1. A part of ''hot'' reactions of mesic atoms with medium is discussed. On the basis of experimental data available it is concluded that its contribution is negligible

[en] The studies were made aimed at systematization of all available experimental data on atomic capture of negative muons by cations and anions in chalcogenides Esub(e)Xsub(m) (X=O,S,Se,Te), halogenides E Halsub(m) (Hal=F, Cl, Br, I) and hydroxides Hsub(m)EOsub(n). By using all experimental probabilities of muon capture available the chemical increment W is tabulated and diagrammatized over the periods and groups of the element E. The capture regularities depending on the charge state the group and period of the element E are traced

[en] The temperature dependence of the muon X-ray spectrum structure is studied in water, ethanol and germanium. The measurements were carried out at room and liquid nitrogen temperature. The transition intensity ratios at two temperatures for the targets studied are tabulated. The results indicate that neither a change in the crystal structure in case of water (crystal-liquid), nor a change in the electric conductivity in case of Ge affect the structure of muon X-ray spectra. It is concluded that the electrons of neighbouring atoms in the chemical bond are responsible for the spectrum modification

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