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A two-channel analyzer of optically dense flammable aerosol fluxes based on two parallel diode optocouplers with a wavelength of electromagnetic radiation λ=0.65 and 3.4 μm, a speed of tau≤ 0.05 s and the transmission of digitized data to a server up to 1200 m away via the RS-485 interface has been developed. Its design and characteristics in the process of detecting particle streams with a diameter of 0.2 to 5000 μm with an optical density of D≤3.5 are described. It is shown that the values of the ratio of wave attenuation coefficients with λ=0.65 and 3.4 μm to the droplet size calculated on the basis of the theory of radiation scattering Mi are consistent with the experimental ones. The created aerosol analyzer can be used in the express analysis of technogenic airborne emissions of fuel liquids and for the development of large-scale generators of explosive type when creating pulse barriers from clouds of finely dispersed aerosol in the atmosphere. Keywords: aerosol analyzer, speed, diode optocouplers, infrared and visible radiation, attenuation factor, optically dense emissions, Mi scattering theory, fuel liquids.

EPECUR experimental setup is aimed at the search of narrow resonant states by precision measurement of differential and total reaction cross sections of pion-nucleon interaction with 1 MeV pion energy steps. In five years passed from the idea of the experiment till the start of the data taking in April of 2009, a new apparatus was build from scratch at the universal beam line 322 of ITEP proton synchrotron U-10. The setup is essentially a non-magnetic spectrometer with a liquid hydrogen target based on the large aperture drift chambers with hexagonal structure. The unique properties of the beam line allow individual pion momentum measurement with the accuracy better than 0.1%. The momentum tagging is done with 1 mm pitch proportional chambers located in the first focus of the beam line. The design of numerous subsystems of the setup is based on modern electronic components including microprocessors and FPGA. All the subsystems are tuned and tested both individually and as parts of the whole working setup. The distributed data acquisition system uses widely spread USB and Ethernet protocols, which allows to achieve high performance and take full advantage of the industrial solutions., Comment: 31 pages, 15 figures, in Russian

An experiment EPECUR, aimed at the search of the cryptoexotic non-strange member of the pentaquark antidecuplet, started its operation at a pion beam line of the ITEP 10 GeV proton synchrotron. The invariant mass range of the interest (1610-1770) MeV will be scanned for a narrow state in the pion-proton and kaon-lambda systems in the formation-type experiment. The scan in the s-channel is supposed to be done by the variation of the incident pi- momentum and its measurement with the accuracy of up to 0.1% with a set of 1 mm pitch proportional chambers located in the first focus of the beam line. The reactions under the study will be identified by a magnetless spectrometer based on wire drift chambers with a hexagonal structure. Because the background suppression in this experiment depends on the angular resolution, the amount of matter in the chambers and setup is minimized to reduce multiple scattering. The differential cross section of the elastic pi-p-scattering on a liquid hydrogen target in the region of the diffractive minimum will be measured with statistical accuracy 0.5% in 1 MeV steps in terms of the invariant mass. For KLambda-production the total cross section will be measured with 1% statistical accuracy in the same steps. An important byproduct of this experiment will be a very accurate study of Lambda polarization. The setup was assembled and tested in December 2008 and in April 2009 we had the very first physics run. About 0.5x10^9 triggers were written to disk covering pion beam momentum range 940-1135 MeV/c., Comment: 4 pages, 4 figures, to appear in the proccedings of DSPIN'09, Dubna, Russia, Sep. 1-5, 2009