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2021 year, number 7
a:2:{s:4:"TYPE";s:4:"HTML";s:4:"TEXT";s:138:"L.N. Sinitsa1, N.M. Emel’yanov1, A.A. Lugovskoi1, A.P. Shcherbakov1, V.V. Annenkov2";}
1V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science Tomsk, Russia 2Limnological Institute of the Siberian Branch of the RAS Irkutsk, Russia
Keywords: nanopores, water vapor, absorption spectrum, regression analysis
Abstract >>
A technique for determining the diameter of nanosized pores has been developed. It consists in filling a substance with liquid water, recording the absorption spectra of the substance with water, compiling a database of spectroscopic data characterizing the substance with different pore sizes, and retriving the pore diameter of an arbitrary substance using an algorithm based on the regression analysis. The technique has been tested on silica samples of different porosity.
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V.P. Kochanov
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science
Keywords: line broadening constants, interaction potential, scattering amplitudes
Abstract >>
A simple version of the theory of line broadening is developed, which makes it possible to numerically and analytically calculate the parameters of collisional line broadening, shifting and narrowing of spectral lines based on the potentials of intermolecular interactions of the Lennard-Jones type. Namely, expressions are derived for the real and imaginary parts of the input and output frequencies of the collision integral, as well as for the line width. The main simplifications are in the model of non-degenerate states and one perturbing level. The eikonal approximation made it possible to express the constants under consideration in terms of the scattering S -matrices based on more general expressions in terms of the scattering amplitudes. The dependences of the considered parameters on the speed of active molecules and gas temperature are determined.
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V.K. Oshlakov, G.G. Matvienko, P.A. Babushkin
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia
Keywords: femtosecond pulse, dispersion, refractive index, nonlinear focus, water vapor
Abstract >>
A model of the dependence of the refractive index of a two-component medium of laser pulse propagation is suggested using the example of a mixture of dry air and water vapor. The model parameters are related to the physical characteristics of the laser pulse and propagation medium. The air refractive index and the related femtosecond laser pulse parameters (dispersion length, nonlinear coefficients, critical power, and nonlinear focus) are calculated for typical values of the volume fraction of water vapor in the atmosphere.
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Yu.E. Geints1, E.K. Panina1, O.V. Minin2, I.V. Minin2
1V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia 2Siberian State University of Geosystems and Technologies, Novosibirsk, Russia
Keywords: Fresnel zone plates, light focusing, focal spot
Abstract >>
The results of the numerical simulations of binary phase Fresnel zone plates (FZP) of mesowavelength sizes and large aperture angles (NA ~ 1) are presented. The simulation allowed us to reveal the main regularities of the formation of the spatial optical near-field structure, as well as to optimize FZP design for obtaining the most intense focus. We show the dimensional parameters of FZP focal region to be sensitive both to the depth of phase zones etching and to the type of structural design of the plate. An increase in the number of Fresnel zones leads to the formation of external local focus with a greater intensity.
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S.M. Sakerin1, D.M. Kabanov1, D.A. Kalashnikova2, I.A. Kruglinsky1, V.I. Makarov3, A.N. Novigatinsky4, V.V. Polkin1, S.A. Popova3, A.O. Pochufarov1, G.V. Simonova2, Yu.S. Turchinovich1, V.P. Shevchenko4
1V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia 2Institute of Monitoring of Climatic and Ecological Systems of the Siberian Branch of the Russian Academy of Sciences, Tomsk, Russia 3V.V. Voevodsky Institute of Chemical Kinetics and Combustion of the Siberian Branch of the RAS, Novosibirsk, Russia 4P.P. Shirshov Institute of Oceanology Moscow, Russia, Moscow, Russia
Keywords: atmosphere over the ocean, aerosol, black carbon, elemental and organic carbon, elemental and isotopic composition
Abstract >>
a:2:{s:4:"TYPE";s:4:"TEXT";s:4:"TEXT";s:633:"We discuss the physicochemical characteristics of aerosol over seas of the North Atlantic and Arctic Ocean measured in the 80th and two preceding (the 67th and 71st) cruises of RV “Akademik Mstislav Keldysh”. Most aerosol characteristics (concentrations of aerosol, black carbon, elemental and organic carbon, elemental composition) are shown to be larger in the atmosphere of the Baltic and North Seas as compared to the Norwegian and Barents Seas. The isotopic composition of carbon in aerosol samples was in the range of light values, indicating the predominance of carbon formed during combustion of oil products and natural gas.";}
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O.E. Bazhenov
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia
Keywords: total ozone content, ozone concentration, ozone anomaly, Aura satellite
Abstract >>
In winter-spring 2019-2020 there was the strongest ozone anomaly in the Arctic in the total history of the ozone observations. It was due to extraordinarily strong and long-lived polar vortex entailing unprecedented chemical ozone destruction. Analysis of Aura OMI/MLS data showed that the total ozone content steadily decreased until having been 230 DU on March 18 at Alert site, 222 DU on March 18 at Eureka, 229 DU on March 20 at Thule, and 226 DU on March 18 at Resolute. The minimal temperature was 9-10% below norm from December to April in the stratosphere over Tomsk and the Arctic. Ozone concentration had been 4% of the long-term mean at altitude of 20 km on March 27 for Eureka and 6% at altitude of 19 km on April 16 for Ny-Ålesund (i.e., about a factor of 30 below). This event is within the context of climate changes leading to cooling of the stratosphere. As far as the level of ozone depleting substances in the stratosphere of the Arctic is above acceptable values, there will be a danger that these events will reoccur in the future. Fortunately, the 2020 vortex was exclusively isolated, which appreciably mitigated its effect on midlatitudes.
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V.F. Raputa, A.A. Lezhenin
Institute of Computational Mathematics and Mathematical Geophysics of the Siberian Branch of the RAS, Novosibirsk, Russia
Keywords: satellite images, smoke plume, buoyancy flux, atmosphere, equations of hydrothermodynamics, height of impurity rise
Abstract >>
A numerical model has been developed for retrieving characteristics of the active phase of the rise of a smoke plume based on observation data. The basic conditions in the estimation model are the solution of the equations of hydrothermodynamics of the atmosphere. Using satellite information, the temperature variation and the rate of rise of the smoke plume from the high-rise pipe of the Gusinoozyorskaya GRES were numerically retrieved. The efficiency of the approach proposed in winter time, which is characterized by large volumes of emissions of smoke mixtures and high contrast of the shadows of the plumes on the earth's surface, is shown.
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V.V. Kalchikhin, A.A. Kobzev, A.A. Tikhomirov, D.E. Filatov
Institute of Monitoring of Climatic and Ecological Systems of the Siberian Branch of the Russian Academy of Sciences, Tomsk, Russia
Keywords: optical precipitation gauge, calibration, drop size, snowstorm parameter gauge
Abstract >>
The dependence of the optical precipitation gauge calibration results on the dimensions of the reference objects is analyzed. The ways to optimize the calibration procedure are suggested, including: reducing the number of calibration zones; use of calibration factors instead of correction parameters; additional calibration with balls with a diameter of 1 mm; use of the coefficients depending on the measured diameter for particles smaller than 2 mm. The conclusion is made about the effectiveness of the calibration procedure suggested for the optoelectronic devices designed to measure the size of small particles, for example, a snowstorm parameter gauge.
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V.P. Vasiliev1, I.V. Znamenskii1, A.A. Tikhomirov2
a:2:{s:4:"TYPE";s:4:"HTML";s:4:"TEXT";s:251:"1Research-and-Production Corporation «Precision Systems and Instruments», Moscow, Russia 2Institute of Monitoring of Climatic and Ecological Systems of the Siberian Branch of the Russian Academy of Sciences, Tomsk, Russia";}
Keywords: laser rangefinder, batch signal, simulation, probabilities of false alarm and correct signal detection
Abstract >>
Processing of batch signals of a laser rangefinder intended for measuring the spacecraft orbit altitude using the pulsed method in the altitude range 180-370 km is simulated for a photodetector operating in the charge-integration mode with allowance for the background solar radiation power. In this case, the rangefinder emits a batch of five 10-ns pulses with a lag between pulses of 250 ms. Digital processing of the received echo signals is based on the method of synchronous post-detector summation of the amplitudes of all pulses in the batch. To simulate the procedure of signal processing, a 180-367.5 km pulse strobe was used. The simulation program which generates normal Gaussian noise with the mean value and the variance depending on the mean background radiation power is described together with the program interface. The probabilities of false alarm and correct signal detection are determined with allowance for the threshold number of photoelectrons for different numbers of signal photoelectrons in a single pulse of the batch. The errors of measuring the altitude range are investigated for the entire strobe.
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M.V. Volkov1,2, V.A. Bogachev1, F.A. Starikov1,2, R.A. Shnyagin1
1Russian Federal Nuclear Center - All-Russian Research Institute of Experimental Physics, Sarov, Russia 2Sarov Physical-Technical Institute of the National Research Nuclear University
Keywords: adaptive optical system, Shack-Hartmann wavefront sensor, phase correction of laser beam, atmospheric turbulence
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The effect of limited operating speed of the adaptive optics system with a Shack-Hartmann wavefront sensor (WFS) on the correction efficiency of dynamical laser beam phase distortions caused by the atmospheric turbulence is numerically studied. Estimation of frequency bandwidth of essential turbulent distortions with the help of WFS has been proposed, which is convenient from a practical point of view.
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V.V. Sychev1, A.I. Klem2, K.I. Korotkova3, O.I. Komarova4
1N.E. Bauman Moscow State Technical University, Moscow, Russia 2JSC "Aviation Holding Company "Sukhoi", Moscow, Russia 3OKB Gidropress JSC State Atomic Energy Corporation Rosatom, Podolsk, Russia 4JSC "TSNIRTI Im. akademika A.I. Berga", Moscow, Russia
Keywords: Large Azimuth Telescope (BTA-6), test of asphere, interferometer, computer generated hologram, pseudo-inversion method, measurement error
Abstract >>
The necessity and possible ways of monitoring the deformations of the primary mirror directly on the BTA telescope during its operation are discussed. The analysis of the most acceptable methods and control schemes is carried out. A scheme is proposed that implements the pseudo-reversal method, which simply and originally solves the control problem based on the experience of AST-1200 telescope with a composite primary mirror. The possible magnitude of the measurement errors of the system proposed for controlling the deformations of the primary mirror is estimated.
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P.A. Konyaev
V.E. Zuev Institute of Atmospheric Optics of Siberian Branch of the Russian Academy of Science, Tomsk, Russia
Keywords: optical-electronic systems, atmospheric turbulence, digital image processing, parallel computational algorithms
Abstract >>
Algorithms for real time two-dimensional digital image processing when observing on atmospheric paths are considered. A procedure for measuring the turbulence parameter directly during of observation is suggested. It can be applied both with the use of a reference object (a radial mire), and without it. An efficient high-speed correlation tracking algorithm with reference frame normalization was applied to correct the image jitter caused by the atmosphere. Blurred image restoration algorithms based on the inverse filterization of angular spatial frequencies are implemented with the use of parallel computing procedures from the Intel® MKL and IPP libraries. The results of computer simulation of digital images blur and its correction are presented, as well as examples of processing experimental video frames on real atmospheric paths.
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