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The astrophysical complex TAIGA (Tunka Advanced Instrument for cosmic-ray physics and Gamma-ray Astronomy), whose first phase is being completed in the Tunka valley 50 km from Lake Baikal, is described. Its research program, first results, and development prospects are discussed.

The importance and advantages of the hybrid approach developed within the TAIGA project for studying the high-energy section of the spectrum of gamma radiation in the Universe are discussed. The pilot complex of the TAIGA gamma observatory with an area of 1 km $${}^{2}$$ is briefly described along with the lines of its development, and the first results obtained on this basis are given.

Tracking Ultraviolet Setup (TUS) detector is a detector of ultraviolet (UV) radiation of the atmosphere in the wavelength range of 300–400 nm (near-ultraviolet) with high sensitivity (tens of photons emitted within the solid angle of 10–4 sr in 0.8 μs), which operated for a year and a half aboard the Lomonosov satellite. The TUS telescope had a multipurpose operational program, which made it possible to detect UV flashes from the shortest ones created by extensive air showers generated by cosmic rays to long ones, up to 1 s, created by meteors. Among these various phenomena, most often are flashes from lightning strikes, both directly creating a glow and causing the development of secondary discharges in the atmosphere, in the upper atmosphere and in the ionosphere. These discharges differ in both nature and phenomenology—in particular, they have different durations and luminosities.

Fourier-transform infra-red spectroscopy with frustrated total internal reflection was used to study radiation-induced processes upon the implantation of boron and phosphorus ions into positive FP9120 diazoquinone-novolac photoresist films on silicon. Strengthening of the photoresist adhesion to monocrystalline silicon was found to be caused by the formation of ester linkages between hydroxyl groups on the surface of the silicon wafer oxide layer and carboxyl groups of 1-H-indene-3-carboxylic acid.

Diazoquinone–novolac photoresist FP9120 films of 1.0–2.5 μm in thickness with boron ions, implanted at an incident ion energy of 60 keV and a fluence of 5 × 1014–1 × 1016 cm−2, have been studied using attenuated total reflection (ATR) FTIR spectroscopy. It has been shown that ion implantation leads to the appearance in the layer beyond the range of ions of intense ATR bands with maxima at 2151 and 2115 cm−1 due to stretching vibrations of C=C=O cumulative double bonds formed as a result of denitrogenation of o‑naphthoquinone diazide. During implantation, a redistribution of intensities was observed between the maxima of the ATR bands due to the terminal methyl groups and methylene groups in favor of the latter. This may indicate radiation crosslinking of novolac resin molecules, involving radicals with the unpaired electron localized at the terminal methyl groups.

The TAIGA experiment (Tunka Advanced Instrument for cosmic ray physics and Gamma-ray Astronomy) combines heterogeneous arrays of imaging and non-imaging Cherenkov light detectors for registration of extensive air showers. Monte Carlo simulation of the whole detector response was carried out and is described in this article.

IACTs are one of the key parts of the TAIGA observatory and designed for study of gamma rays and charged cosmic rays in the energy range of 10 $${}^{13}{-}10^{18}$$ eV. The first IACT was designed and fabricated at the JINR workshop and has been operating since 2016 in the Tunka valley. The second one has been assembled there at September 2018 and the production of the third one is in progress to be transported to the Tunka valley in August 2019. The R&D to fabricate focusing glass mirrors directly in JINR is underway. The report presents the TAIGA IACT main characteristics and the results of the comparison between the JINR glass mirrors and composite mirrors (Media Lario company, Italy).

The TUS experiment is aimed to study the energy spectrum and arrival direction of Ultra High Energy Cosmic Rays at E ∼ 100 EeV from the space orbit by measuring the fluorescence radiation of the Extensive Atmospheric Shower in the atmosphere. It is the first orbital telescope aimed for such measurements and is taking data since April 28, 2016. During the first turns of operation ∼20% PMTs were broken due to the HV tuning system failure. For the same reason, the properties of the remaining PMTs are changed. Relative calibration of PMT gains in flight was done and presented based on analyzing TUS background data itself. A reconstruction of EAS arrival directions is done using the relative calibration coefficients.

The Tunka-133 Cherenkov complex for recording extensive air showers (EAS) collected data over seven winters from 2009 to 2017. The differential energy spectra of all particles was acquired in the 6 × 1015–3 × 1018 eV range of energies over 2175 h. The TAIGA-HiSCORE complex is continually being expanded and upgraded. Data acquired by 30 first-line stations over 35 days during the period 2017–2018 is analyzed in this work. As at the Tunka-133 setup, the primary particle energies above 1015 eV are measured using the density of the Cherenkov light flux at a distance of 200 m from a shower’s axis. Data on lower energies are collected by determining the energy of the light flux near a shower’s axis. This results in a spectrum of 2 × 1014–1017 eV. The combined spectrum for the two systems covers a range of 2 × 1014–2 × 1018 eV.

The TAIGA (Tunka Advanced Instrument for cosmic ray physics and Gamma-ray Astronomy) experiment aims at observing gamma-rays in the energy range from 1 TeV to several 100 TeV. The operation of the observatory is based on a new hybrid approach that combines imaging air Cherenkov telescopes (IACTs) and wide-angle Cherenkov detectors (TAIGA-HiSCORE) for measuring times of extensive air shower (EAS) light front arrival. Monte Carlo simulations are compared to real data to determine the performance of the detector setup. Dedicated software and algorithms are described, model parameters are given, and an overview of the current status of model-based performance studies is presented.

The TUS (Tracking Ultraviolet Setup) detector aboard the Lomonosov satellite was launched into a Sun-synchronous orbit with an altitude of ~500 km on April 28, 2016. The main purpose of the TUS orbital experiment is to search for ultra-high energy cosmic rays (UHECRs) with Е > 70 EeV by measuring the fluorescence and Cherenkov radiation of extensive air showers (EASes) in the Earth’s atmosphere. The design and operating principles of the TUS detector are briefly described. A multilevel algorithm developed to search for and reconstruct EAS events (candidates) in the region of UHECRs is used to analyze the TUS data. Preliminary results from the TUS in orbit, including the results from the search for and study of identified EAS candidates, are presented.

The relevance and benefits of the new TAIGA gamma observatory complex in the Tunka Valley (50 km from Lake Baikal) are discussed. The main aim of the TAIGA installation is to study high-energy gamma radiation and search for cosmic pevatrons. The first series of gamma stations was commissioned in 2019 and covers an area of 1 km2. Its expected integral gamma radiation sensitivity at an energy of 100 TeV over 300 h of source monitoring is (2–5) × 10−13 TeV cm−2 s−1. It is planned to expand the effective area of TAIGA gamma observation to 10 km2 in the future.

A new knee-like approximation of the lateral distribution function (LDF) of EAS Cherenkov light in the 30–3000 TeV energy range was proposed and tested with simulated showers in our earlier studies. This approximation fits the LDFs of individual showers accurately for all types of primary particles gamma-rays, protons, and nuclei) and is suitable for reconstructing the shower core, determining the energy, and separating gamma-induced showers from hadron-induced ones. In the present study, the knee-like fitting function is used to determine the parameters of real showers detected by TAIGA-HiSCORE. It is demonstrated that this approximation characterizes properly all types of individual LDFs of experimental events in the 300–1000 TeV range. The accuracy of fit is governed by fluctuations intrinsic to the process of measurement of the Cherenkov photon density. The probability density function of these fluctuations was reconstructed and introduced into simulations. Certain useful methodical applications of the knee-like approximation are con-sidered, and the possibility of shower sorting into nuclei groups is examined. The extensive statistical coverage and detailed LDF measurement data of HiSCORE have provided the first opportunity to examine in depth the LDF of Cherenkov radiation in the 300–1000 TeV range.

The aim of research is to study the phyto and sanitary conditions of green space and the development for its improvement to ensure the appropriate level of further functioning of the park in Chortkiv. The inventory of green space was made in accordance with existing instruction by Technical Greenery Inventory. Plants were determined by conventional methods. To characterize the state of the plant taxations we defined the following parameters: the diameter and height of trees as well as different methods concerning the status of the vitality of plants. The conventional method was used to determine the defectiveness of trees. The criteria for evaluation of the ecological and decorative wood characteristics were as folows: height, trunk diameter, crown diameter and evaluation of vitality. It was used by traditional and modern instruments. The modern were tools were as follows: global positioning device (GPS), geographic information systems (GIS), and methods of remote sensing (on the basis of an orthophotoplan which was obtained with the help of a quadcopter Phantom 4). The data on the location of each tree received via GPS Garmin GPS Map 64S with its subsequent adjustments based on RS Landsat in GIS ArcGis 9.2. After that, GIS database of trees and shrubs was obtained, including coordinates of tree location combined with the information about species, phytosanitary and fundamental taxation features. This enables storing it in a digital format. It gives us opportunity of automated study of the data and displaying them in the form of discrete information on a map. Using these capabilities and digital elevation models, we have created the 3-dimensional digital model of the territory in the license version of RLA2014. After that, to the program layout-creation we put the trees and shrub vegetation according to their location, species and age composition with using of existing GIS database information. The park conditions were analyzed and evaluated considering the phytosanitary, productive and aesthetic conditions. The types of garden landscapes of the object were identified. The analysis of the phytosanitary state of green plantations in Chortkiv Park showed that the vast majority of trees belonged to the category of "good" and almost a quarter of the trees needed to be sanitized or removed.

Over the past few years, the TAIGA (Tunka Advanced Instrument for cosmic ray physics and Gamma-ray Astronomy) observatory has been being deployed in the Tunka Valley, Republic of Buryatia. It is designed for studying gamma rays of energy above 30 TeV and performing searches for sources of galactic cosmic rays with energies in the vicinity of 1 PeV, which is an energy region around the classic knee in the cosmic-ray energy spectrum. The first phase of the observatory will be situated at a distance of about 50 km from Lake Baikal at the site of the Tunka-133 array. The TAIGA gamma observatory will include a network of 500 wide-angle (0.6 sr) Cherenkov detectors (TAIGA-HiSCORE array) and up to 16 atmospheric Cherenkov telescopes (ACT) designed for analyzing the EAS images (imaging atmospheric Cherenkov telescopes, or IACT) and positioned within an area of 5 km2. The observatory will also include muon detectors of total area 2000 m2 distributed over an area of 1 km2. Within the next three years, it is planned to enhance the area of the TAIGA-HiSCORE array by a factor of four—from 0.25 km2 to 1 km2; to supplement the existing IACT with two new ones; and to deploy new muon detectors with a total coverage of 200 m2. The structure of the new observatory is described along with the data analysis techniques used. The most interesting physical results are presented, and the research program for the future is discussed.

The article presents the relevance and advantages of the new gamma observatory TAIGA (Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy), which is being constructed in the Tunka Valley 50 km from Lake Baikal. Various detectors of the six TAIGA gamma observatory arrays register the Cherenkov and radio radiation, as well as the electron and muon components of EAS. The primary objective of the TAIGA gamma observatory is to study the high-energy part of the gamma-ray spectrum, in particular, in order to search for Galactic PeVatrons. The energy, direction, and position of the EAS axis are reconstructed in the observatory based on the data of the wide-angle Cherenkov detectors of the TAIGA-HiSCORE experiment. Taking into account this information, the gamma quanta are distinguished from the hadron background using the data obtained by the muon detectors and telescopes that register the EAS image in the Cherenkov light. In this hybrid mode of operation, the atmospheric Cherenkov telescopes can operate in the mono-mode, and the distance between them can be increased to 800–1000 m, which makes it possible to construct an array with an area of 5 km2 and more at relatively low cost and in a short time. By 2019, the first stage of the gamma observatory with an area of 1 km2 will be constructed; its expected integral sensitivity for detecting the gamma radiation with an energy of 100 TeV at observation of the source for 300 hours will be approximately $$2 \times 5$$ 10–13 TeV cm–2s–1.

TAIGA (Tunka Advanced Instrument for Gamma Astronomy) is designed for studying gamma rays and charged cosmic particles in the energy range of 1013–1018 eV. The staff of the Joint Institute for Nuclear Research is now working on the design and fabrication of Cherenkov telescope elements (IACTs). The IACT field of view is ~10° × 10°, due to a Davis–Cotton optical layout with 34 mirrors 0.60 m in diameter, a focal length of 4.75 m, and 560 XP1911 PMT camera. The first IACT was commissioned in 2016 in the Tunka Valley. The second IАСТ is now being prepared for operation. The steps of PMT alignment and the results from its calibration are thoroughly described along with the fabrication of a mirror and its optical parameters. The technique for adjusting the mirror is presented as well. It replaces the conventional visual assessment of the image with pattern recognition software that is applied to a screen shot of the calibration source. This software ensures highly precise calculations of the mirror’s adjusting screws to obtain a correct image.

It is planned that new TAIGA-Muon detectors will complement the existing Tunka-GRANDE facility of scintillation detectors of the TAIGA gamma-observatory in the Tunka valley, Russia. The new design of scintillation detector with wavelength shifting bars and PMTs is developed. The first prototype of the counter was installed and tested using infrastructure of the Tunka-GRANDE installation in 2017. The mass production of counters has begun in 2018 at the Novosibirsk State University.

The TUS space experiment is aimed at studying energy and arrival distribution of UHECR at E > 7 × 1019 eV by using the data of EAS fluorescent radiation in atmosphere. The TUS mission was launched at the end of April 2016 on board the dedicated “Lomonosov” satellite. The TUSSIM software package has been developed to simulate performance of the TUS detector for the Fresnel mirror optical parameters, the light concentrator of the photo detector, the front end and trigger electronics. Trigger efficiency crucially depends on the background level which varies in a wide range: from 0.2 × 106 to 15 × 106 ph/( m 2 μ s sr) at moonless and full moon nights respectively. The TUSSIM algorithms are described and the expected TUS statistics is presented for 5 years of data collection from the 500 km solar-synchronized orbit with allowance for the variability of the background light intensity during the space flight.

The design for the TAIGA-HiSCORE array, a part of the TAIGA Gamma Ray Observatory, is considered. The observatory is being constructed in the Tunka Valley, 50 km from Lake Baikal. Preliminary results obtained using the first 28 optical stations of the array are presented.

One of the most informative methods of cosmic ray studies is the detection of Cherenkov light from extensive air showers (EAS). The primary energy reconstruction is possible by using the Earth’s atmosphere as a huge calorimeter . The EAS Cherenkov light array Tunka-133, with ∼ 3 km 2 geometrical area, is taking data since 2009. Tunka-133 is located in the Tunka Astrophysical Center at ∼ 50 km west of Lake Baikal. This array allows us to perform a detailed study of the energy spectrum and the mass composition in the energy range from 6 ⋅ 1 0 15 eV to 1 0 18 eV . Most of the ongoing efforts are focused on the construction of the first stage of the detector TAIGA (Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy). The latter is designed for the study of gamma rays and charged cosmic rays in the energy range of 1 0 13 eV – 1 0 18 eV . The TAIGA prototype will consist of ∼ 100 wide angle timing Cherenkov stations (TAIGA-HiSCORE) and three IACTs deployed over an area of ∼ 1 km 2 . The installation of the array is planned to be finished in 2019 while the data-taking can start already during the commissioning phase. The joint reconstruction of energy, direction, and core position of the imaging and non-imaging detectors will allow us to increase the distance between the IACTs up to 800 m, therefore providing a low-cost, highly sensitive detector. The relatively low cost together with the high sensitivity for energies ≥ 30–50 TeV make this pioneering technique very attractive for exploring galactic PeVatrons and cosmic rays. In addition to the Cherenkov light detectors we intend to deploy surface and underground muon detectors over an area of 1 km 2 with a total area of about 1000 m 2 . The results of the first season of coincident operation of the first ∼ 4 m diameter IACT with an aperture of ∼ 10°with 30 stations of TAIGA-HiSCORE will be presented.

The TUS telescope, part of the scientific equipment on board the Lomonosov satellite, is the world’s first orbital detector of ultra-high energy cosmic rays. Preliminary results from analyzing unexpected powerful signals that have been detected from the first days of the telescope’s operation are presented. These signals appear simultaneously in time intervals of around 1 μs in groups of adjacent pixels of the photodetector and form linear track-like sequences. The results from computer simulations using the GEANT4 software and the observed strong latitudinal dependence of the distribution of the events favor the hypothesis that the observed signals result from protons with energies of several hundred MeV to several GeV passing through the photodetector of the TUS telescope.

We investigate the phase transition of Bose–Einstein particles with the hard-core repulsion in the grand canonical ensemble within the Van der Waals approximation. It is shown that the pressure of non-relativistic Bose–Einstein particles is mathematically equivalent to the pressure of simplified version of the statistical multifragmentation model of nuclei with the vanishing surface tension coefficient and the Fisher exponent тF = 5/2 , which for such parameters has the 1-st order phase transition. The found similarity of these equations of state allows us to show that within the present approach the high density phase of Bose-Einstein particles is a classical macro-cluster with vanishing entropy at any temperature which, similarly to the system of classical hard spheres, is a kind of solid state. To show this we establish new relations which allow us to identically represent the pressure of Fermi–Dirac particles in terms of pressures of Bose–Einstein particles of two sorts.

The temperature dependence of the coefficient of tunneling through the Coulomb barrier is estimated for nuclei of the hydrogen isotopes at comparatively low temperatures using a model of screened Coulomb interaction potential between the isotopes put inside an external oscillator potential well. The temperature dependences for the tunneling coefficient are calculated for pp-, pd-, pt-, dd-, and dt-processes at different screening radii. The probable role of pp-reactions is discussed.

The TAIGA observatory addresses ground-based gamma-ray astronomy at energies from a few TeV to several PeV, cosmic ray physics from 100 TeV to several EeV as well as for search for axion-like particles, Lorentz violations and another evidence of New Physics. In 2020 year a one square kilometer TAIGA setup should be put in operation.

International Conference on Instrumentation for Colliding Beam Physics, INSTR20, Novosibirsk, Russia, 24 Feb 2020 - 28 Feb 2020; Journal of Instrumentation 15(06), C06057 (2020). doi:10.1088/1748-0221/15/06/C06057, The TAIGA-Muon scintillation array is located in the Tunka Valley. It is a part of the single TAIGA experimental complex. Its construction has started in the summer of 2019. By the autumn of 2019, the first three clusters were installed. We describe the design of the TAIGA-Muon array, the data acquisition (DAQ) sistem, reading and control systems., Published by Inst. of Physics, London

The combination of a wide angle timing Cherenkov array and Imaging Atmospheric Cherenkov Telescopes operated in mono mode offers a cost-effective way to construct a few square kilometers array for ultrahigh-energy gamma astronomy. The first stage of the TAIGA Observatory (Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy) is described here. It will comprise TAIGA-HiSCORE - 120 wide angle Cherenkov stations distributed over an area of 1.0 km2 and three IACTs (TAIGA-IACT).

The multiplicities of light (anti)nuclei were measured recently by the ALICE collaboration in Pb+Pb collisions at the center-of-mass collision energy $\sqrt{s_{NN}} =2.76$ TeV. Surprisingly, the hadron resonance gas model is able to perfectly describe their multiplicities under various assumptions. For instance, one can consider the (anti)nuclei with a vanishing hard-core radius (as the point-like particles) or with the hard-core radius of proton, but the fit quality is the same for these assumptions. In this paper we assume the hard-core radius of nuclei consisting of $A$ baryons or antibaryons to follow the simple law $R(A) = R_b (A)^\frac{1}{3}$, where $R_b$ is the hard-core radius of nucleon. To implement such a relation into the hadron resonance gas model we employ the induced surface tension concept and analyze the hadronic and (anti)nuclei multiplicities measured by the ALICE collaboration. The hadron resonance gas model with the induced surface tension allows us to verify different scenarios of chemical freeze-out of (anti)nuclei. It is shown that the most successful description of hadrons can be achieved at the chemical freeze-out temperature $T_h=150$ MeV, while the one for all (anti)nuclei is $T_A=168.5$ MeV. Possible explanations of this high temperature of (anti)nuclei chemical freeze-out are discussed., Comment: 6 pages, 1 figure

The chemical freeze-out irregularities found with the most advanced hadron resonance gas model and possible signals of two QCD phase transitions are discussed. We found that the center-of-mass collision energy range of tricritical endpoint of QCD phase diagram is [9; 9.2] GeV which is consistent both with QCD inspired exactly solvable model and with experimental findings., Comment: 6 pages, 2 figures

The spatial structure of $^{14}$N nucleus is studied within a five-particle model (three $\alpha$-particles plus two nucleons). Using the variational approach with Gaussian bases, the ground-state energy and wave function are calculated for this five-particle system. Two spatial configurations in the ground-state wave function are revealed. The density distributions, pair correlation functions, and the momentum distributions of particles are analyzed and compared with those of the mirror nuclei $^{14}$C and $^{14}$O., Comment: arXiv admin note: substantial text overlap with arXiv:1611.07949

The physics motivations and advantages of the new TAIGA (Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy) detector are presented. TAIGA aims at gamma-ray astronomy at energies from a few TeV to several PeV, as well as cosmic ray physics from 100 TeV to several EeV. For the energy range 30 – 200 TeV the sensitivity of 10 km2 area TAIGA array for the detection of local sources is expected to be 5 × 10-14 erg cm-2 sec-1 for 300 h of observations. Reconstruction of the given EAS energy, incoming direction and its core position, based on the timing TAIGA-HiSCORE data, allows one to increase a distance between the IACTs up to 600-1000 m. The low investments together with the high sensitivity for energies ≥ 30-50 TeV make this pioneering technique very attractive for exploring the galactic PeVatrons and cosmic rays. At present the TAIGA first stage has been constructed in Tunka valley, 50 km West from the Lake Baikal. The first experimental results of the TAIGA first stage are presented.

The orbital detector TUS (Tracking Ultraviolet Setup) with high sensitivity in near-visible ultraviolet (tens of photons per time sample of 0.8 μ s of wavelengths 300−400 nm from a detector’s pixel field of view) and the microsecond-scale temporal resolution was developed by the Lomonosov-UHECR/TLE collaboration and launched into orbit on 28 April 2016. A variety of different phenomena were studied by measuring ultraviolet signals from the atmosphere: extensive air showers from ultra-high-energy cosmic rays, lightning discharges, transient atmospheric events, aurora ovals, and meteors. These events are different in their origin and in their duration and luminosity. The TUS detector had a capability to conduct measurements with different temporal resolutions (0.8 μ s, 25.6 μ s, 0.4 ms, and 6.6 ms) but the same spatial resolution of 5 km. Results of the TUS detector measurements of various atmospheric emissions are discussed and compared to data from previous experiments.

The “Lomonosov” space project is lead by Lomonosov Moscow State University in collaboration with the following key partners: Joint Institute for Nuclear Research, Russia, University of California, Los Angeles (USA), University of Pueblo (Mexico), Sungkyunkwan University (Republic of Korea) and with Russian space industry organizations to study some of extreme phenomena in space related to astrophysics, astroparticle physics, space physics, and space biology. The primary goals of this experiment are to study: - Ultra-high energy cosmic rays (UHECR) in the energy range of the Greizen-Zatsepin-Kuzmin (GZK) cutoff; - Ultraviolet (UV) transient luminous events in the upper atmosphere; - Multi-wavelength study of gamma-ray bursts in visible, UV, gamma, and X-rays; - Energetic trapped and precipitated radiation (electrons and protons) at low-Earth orbit (LEO) in connection with global geomagnetic disturbances; - Multicomponent radiation doses along the orbit of spacecraft under different geomagnetic conditions and testing of space segments of optical observations of space-debris and other space objects; - Instrumental vestibular-sensor conflict of zero-gravity phenomena during space flight. This paper is directed towards the general description of both scientific goals of the project and scientific equipment on board the satellite. The following papers of this issue are devoted to detailed descriptions of scientific instruments.

The origin and nature of extreme energy cosmic rays (EECRs), which have energies above the 50 EeV, the Greisen-Zatsepin-Kuzmin (GZK) energy limit, is one of the most interesting and complicated problems in modern cosmic-ray physics. Existing ground-based detectors have helped to obtain remarkable results in studying cosmic rays before and after the GZK limit, but have also produced some contradictions in our understanding of cosmic ray mass composition. Moreover, each of these detectors covers only a part of the celestial sphere, which poses problems for studying the arrival directions of EECRs and identifying their sources. As a new generation of EECR space detectors, TUS (Tracking Ultraviolet Set-up), KLYPVE and JEM-EUSO, are intended to study the most energetic cosmic-ray particles, providing larger, uniform exposures of the entire celestial sphere. The TUS detector, launched on board the Lomonosov satellite on April 28, 2016, from Vostochny Cosmodrome in Russia, is the first of these. It employs a single-mirror optical system and a photomultiplier tube matrix as a photo-detector and will test the fluorescent method of measuring EECRs from space. Utilizing the Earth's atmosphere as a huge calorimeter, it is expected to detect EECRs with energies above 100 EeV. It will also be able to register slower atmospheric transient events: atmospheric fluorescence in electrical discharges of various types including precipitating electrons escaping the magnetosphere and from the radiation of meteors passing through the atmosphere. We describe the design of the TUS detector and present results of different ground-based tests and simulations., Comment: 19 pages; v2: figures 6 and 9 replaced to match the published version

We present the current status of high-energy cosmic-ray physics and gamma-ray astronomy at the Tunka Astrophysical Center (AC). This complex is located in the Tunka Valley, about 50 km from Lake Baikal. Present efforts are focused on the construction of the first stage of the gamma-ray observatory TAIGA - the TAIGA prototype. TAIGA (Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy) is designed for the study of gamma rays and charged cosmic rays in the energy range 1013 eV–1018 eV. The array includes a network of wide angle timing Cherenkov stations (TAIGA-HiSCORE), each with a FOV = 0.6 sr, plus up to 16 IACTs (FOV - 10∘× 10∘). This part covers an area of 5 km2. Additional muon detectors (TAIGA-Muon), with a total coverage of 2000 m2, are distributed over an area of 1 km2.

This work is a methodical study of another option of the hybrid method originally aimed at gamma/hadron separation in the TAIGA experiment. In the present paper this technique was performed to distinguish between different mass groups of cosmic rays in the energy range 200 TeV - 500 TeV. The study was based on simulation data of TAIGA prototype and included analysis of geometrical form of images produced by different nuclei in the IACT simulation as well as shower core parameters reconstructed using timing array simulation. We show that the hybrid method can be sufficiently effective to precisely distinguish between mass groups of cosmic rays., Comment: 6 pages, 3 figures; proceedings of the 2nd International Conference on Particle Physics and Astrophysics (ICPPA-2016)

The structure of mirror $^{14}$C and $^{14}$O nuclei has been studied in the framework of the five-particle model (three $\alpha$-particles and two nucleons). Interaction potentials are proposed, which allowed the energy and radius of $^{14}$C nucleus, as well as the energy of $^{14}$O one, to agree with experimental data. On the basis of the variational approach with the use of Gaussian bases, the energies and wave functions for five-particle systems under consideration are calculated. The charge radius of $^{14}$O nucleus, as well as the charge density distributions and the form factors for both nuclei, are predicted.

We present physical motivations and advantages of the new gamma-observatory TAIGA (Tunka Advanced Instrument for cosmic ray physics and gamma-ray astronomy). TAIGA will be located in the Tunka valley, 50 km to the west of Lake Baikal, at the same place as the integrating air Cherenkov detector for cosmic rays Tunka-133. The TAIGA array is a complex, hybrid detector for ground-based gamma-ray astronomy for energies from a few TeV to several PeV as well as for cosmic ray studies from 100 TeV to several EeV. The array will consist of a wide angle Cherenkov array – TAIGA-HiSCORE with 5km2 area, a net of 16 IACT telescopes (with FOV of about 9.72°×9.72°) as well as muon and other detectors. We present the current status of the array construction.

In this work we discuss a novel approach to model the hadronic and nuclear matter equations of state using the induced surface tension concept. Since the obtained equations of state, classical and quantum, are among the most successful ones in describing the properties of low density phases of strongly interacting matter, they set strong restrictions on the possible value of the hard-core radius of nucleons. Therefore, we perform a detailed analysis of its value which follows from hadronic and nuclear matter properties and find the most trustworthy range of its values: the hard-core radius of nucleons is 0.30--0.36 fm. A comparison with the phenomenology of neutron stars implies that the hard-core radius of nucleons has to be temperature and density dependent., 12 pages, 4 figures, references added, typos corrected

Novomoskovsk is one of the main centers of chemical industry in central Russia. In 2000 to control and monitor the region air quality and movement the atmosphere ecomonitorin system was created. These systems’ modifying lies in using more sophisticated technology, increasing number of observation stations and automatic sensors that determine harmful impurities. The data adequacy of airspace’s state hinges on the number of these stations and their location. The objective of our study is to estimate the data adequacy relying on modern research methods. The research involved the interpolation method of air movement control over areas which have a mixed landscape because of technology-related accidents. The method consists of 3 main stages: experimental examination of the area’s weather conditions, processing of this data using the method of air flow field recovery, and effective control of the air dynamics at man-made accidents. Air control stations gave the initial measures and current data to develop the method of air flow field recovery on the basis of the noise-resistant interpolation principle. Noise-resistant interpolation admits to errors of measuring instruments, which makes a significant magnitude when estimating meteorological data of the air. The data obtained requires to modify Novomoskovsk ecomonitoring system of the atmosphere.

The extensive air shower Cherenkov light array Tunka-133 collected data during 7 winter seasons from 2009 to 2017. From 2175 hours of data taking, we derived the differential energy spectrum of cosmic rays in the energy range 6 · 1015 2 · 1018 eV. The TAIGA-HiSCORE array is in the process of continuous expansion and modernization. Here we present the results obtained with 28 stations of the first HiSCORE stage from 35 clear moonless nights in the winter of 2017-2018. The combined spectrum of two arrays covers a range of 2 · 1014 – 2 · 1018 eV.

We study the role of the nonperturbative input to the transverse momentum dependent (TMD) gluon density in hard processes at the LHC. We derive the input TMD gluon distribution at a low scale ${\ensuremath{\mu}}_{0}^{2}\ensuremath{\sim}1\text{ }\text{ }{\mathrm{GeV}}^{2}$ from a fit of inclusive hadron spectra measured at low transverse momenta in $pp$ collisions at the LHC and demonstrate that the best description of these spectra for larger hadron transverse momenta can be achieved by matching the derived TMD gluon distribution with the exact solution of the Balitsky-Fadin-Kuraev-Lipatov equation obtained at low $x$ and small gluon transverse momenta outside the saturation region. Then, we extend the input TMD gluon density to higher ${\ensuremath{\mu}}^{2}$ numerically using the Catani-Ciafoloni-Fiorani-Marchesini gluon evolution equation. Special attention is paid to phenomenological applications of the obtained TMD gluon density to some LHC processes, which are sensitive to the gluon content of a proton.

TUS (Tracking Ultraviolet Set-up), the first orbital detector of extreme energy cosmic rays (EECRs), those with energies above 50 EeV, was launched into orbit on April 28, 2016, as a part of the Lomonosov satellite scientific payload. The main aim of the mission is to test a technique of registering fluorescent and Cherenkov radiation of extensive air showers generated by EECRs in the atmosphere with a space telescope. We present preliminary results of its operation in a mode dedicated to registering extensive air showers in the period from August 16, 2016, to November 4, 2016. No EECRs have been conclusively identified in the data yet, but the diversity of ultraviolet emission in the atmosphere was found to be unexpectedly rich. We discuss typical examples of data obtained with TUS and their possible origin. The data is important for obtaining more accurate estimates of the nocturnal ultraviolet glow of the atmosphere, necessary for successful development of more advanced orbital EECR detectors including those of the KLYPVE (K-EUSO) and JEM-EUSO missions., 18 pages; v2: references fixed; v3: minor changes to address referee's comments