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The current trend in dietary supplements and functional foods is the use of lipophilic bioactive compounds. The sea buckthorn (Hippóphae rhamnoídes) contains some such compounds: polyunsaturated fatty acids, tocopherols, and carotenoids. Lipophilic components are best distributed using oil-in-water emulsions, which ensures their high bioavailability. A significant property of emulsions is colloidal and oxidative stability, so the choice of emulsifiers that have both surface-active properties and antioxidant activity is an important area of research for making new types of food emulsions. The purpose of this study is the development and refinement of an emulsified biologically active food additive containing sea buckthorn products (pulp, juice, and oil) and stabilized with soy phospholipids. We studied the fruits of Chuyskaya, Orange, and Prevoskhodnaya sea buckthorn varieties growing in the Altai Territory. As we analyzed their composition, we chose the Chuyskaya variety for making the emulsion. The fruits contain 5.30 ± 0.1% of lipids including 16.8 ± 0.5 mg/100 g of carotenoids and 10.5 ± 0.5 mg/100 g of tocopherols. To choose the emulsifier we studied the fractional and fatty acid composition of the soy and sunflower phospholipids with different hydrophilic-lipophilic balances (HLB). We made the emulsions containing sea buckthorn oil and pulp of its different layers, soybean oil, and phospholipids by dispersion using an HG-15D homogenizer. The study of the colloidal stability showed that the most stable (99.5%) are the emulsions containing a mixture of hydrolyzed soybean phospholipids (HLB = 7) and fractionated soybean phospholipids (HLB = 3). The best ratio is 40:60. We examined the oxidative stability of the emulsions by provoking accelerated oxidation. The emulsions containing 1.5% of a soy phospholipids mixture showed the best oxidative stability. The resulting direct oil-in-water fine emulsion contains polyunsaturated fatty acids (PUFAs), tocopherols, β-carotene, and essential phospholipids. For this reason, the emulsion can be used to make biologically active food supplements (also encapsulated) and as part of special nutrients.

The TAIGA observatory addresses ground-based gamma-ray astronomy at energies from a few TeV to several PeV, as well as cosmic ray physics from 100 TeV to several EeV and astroparticle physics. The TAIGA experiment current status, recent results and development prospects are presented.

The scintillation experiment of the TAIGA astrophysical complex comprises two systems: Tunka-Grande and Taiga-Muon. The main objective of these systems is to study the energy spectrum and mass composition of cosmic rays in the energy range of eV, as well as to search for gamma radiation in the same energy range. An additional task of the experiments is to search for a signal from gamma quanta in the sub-PeV energy range in conjunction with wide angle Cherenkov detectors TAIGA-HiSCORE and Tunka-133. The report presents the objectives and status of the facility and a description of the design of scintillation counters and clusters. The results of the study of EAS with an unusual spatiotemporal structure are presented together with the results of a study of the joint operation of the Tunka-Grande and TAIGA-HiSCORE setups in order to search for sub-PeV gamma quanta. Estimates are made of the expected number of registered gamma quanta from the Crab Nebula.

This paper proposes a method for separation the light component of cosmic rays in the energy range of 200 TeV–20 PeV (the knee region in the PCR spectrum) from hybrid events detected by two Cherenkov setups IACT + HiSCORE in TAIGA experiment. The possibility of such separation is demonstrated using Monte Carlo calculations and the first experimental estimates are made.

The more correct recalculation from the measured Cherenkov light fluxes at distances of 200 (Q200) and 100 (Q100) m from the Extensive Air Shower (EAS) core to the energy of the primary particle has been developed using the results of M-C simulation by the CORSIKA code, assuming a light primary composition of cosmic rays. Using the new conversion expressions, a differential energy spectrum was obtained according to the data of the Tunka-133 array for 7 years of operation and the TAIGA-HiSCORE array for 2 years of operation.

An analysis is performed of the spectrum of gamma rays from the Crab Nebula in the 4–100 TeV range of energies, obtained using data from two Atmospheric Cherenkov Telescopes that are part of the TAIGA complex. A way of selecting and restoring the energy of gamma rays is described that includes a procedure for restoring the energy spectrum.

— The paper is devoted to the modeling and analysis of data detected by the TAIGA-IACT installation in the stereo mode. Five Imaging Atmospheric Cherenkov Telescopes (IACT) with a viewing angle of 9.6° are expected to be included in the installation. Today there are three telescopes spaced far apart (from 320 to 500 m) in the installation. The effective area of the installation is as large as 0.6 km 2 ; therefore, it is possible to conduct statistically significant measurements of weak γ-ray sources in the energy range above 10 TeV over a reasonable observation time (300–400 h). The Monte Carlo procedure for simulating the hadrons and γ-rays detected by the telescopes is described as is the procedure for reconstructing the parameters of extensive air showers, such as the arrival direction of an event, the axis position, the depth of the maximum of shower development ( X max ), and the primary-particle energy. In order to solve the problem of γ-hadron separation, the criteria for selecting γ-rays detected in the stereo mode have been optimized and the effective area of the installation has been calculated.

The Tunka Radio Extension (Tunka-Rex) is a digital antenna array, which measures radio emission of the cosmic-ray air-showers in the frequency band of 30-80 MHz. Tunka-Rex is co-located with the TAIGA experiment in Siberia and consists of 63 antennas, 57 of them are in a densely instrumented area of about 1 km 2 . In the present workwe discuss the improvements of the signal reconstruction applied for Tunka-Rex. At the first stage we implemented matched filtering using averaged signals as template. The simulation study has shown that matched filtering allows one to decrease the threshold of signal detection and increase its purity. However, the maximum performanceof matched filtering is achievable only in case of white noise, while in reality the noise is not fully random due to different reasons. To recognize hidden features of the noise and treat them, we decided to use convolutional neural network with autoencoder architecture. Taking the recorded trace as an input, the autoencoder returns denoised traces, i.e. removes all signal-unrelated amplitudes. We present the comparison between the standard method of signal reconstruction, matched filtering and the autoencoder, and discuss the prospects of application of neural networks for lowering the threshold of digital antenna arrays for cosmic-ray detection.

The current status of the equipment development for the new wide-angle gamma-ray imaging air Cherenkov telescope for TAIGA hybrid installation is presented. A front-end electronic and data acquisition system board based on the Zynq family Xilinx FPGA chips specially designed for this project have been produced and are being tested. A detailed description if presented for internal structure of the four main subsystems: four 8-channel 100 MHz ADCs, board’s control system, internal clock and synchronization system and the power supply system. Additionally, the current status of a small scale prototype telescope SIT consisting of 49 SiPM is presented. The telescope includes a digital camera for observing the stars and weather condition. The SIT-HiSCORE synchronization systems and the telemetry information collection had been tested.

In TAIGA Observatory (Tunka Advanced Instrument for cosmic ray physics and Gamma-ray Astronomy) we are commissioning the first Imaging Atmospheric Cherenkov Telescope (IACT). The telescope has an alt-azimuth mount and 17-bit shaft encoder for each axis, stepper motors are used for axis control. For the pointing calibration of the telescope a CCD-camera is installed on the dish of the telescope and its position allows to capture simultaneously both the Cherenkov camera with LEDs and the sky with observed source. Since October 2017, the telescope has been operating in tracking mode. In this work the TAIGAIACT telescope pointing calibration approach and first results of the tracking operations are described.