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The results of a study of some ways to improve spectroscopy characteristics of the CdZnTe quasi-hemispherical detectors when working in high gamma radiation fluxes are presented. It was shown that the use of IR illumination with a wavelength of 1050 nm or 1200 nm or at slight warm-up of the detector to +30°C … +40°C can significantly improve spectroscopy performance of the CdZnTe detectors of size 3.5 mm × 3.5 mm × 1.75 mm when operating in a tested gamma-radiation field with a dose rate up to 590 mGy/h.

The search for short-lived particles is usually the final stage in the chain of event reconstruction and precedes event selection when operating in online mode or physics analysis when operating in offline mode. Most often such short-lived particles are neutral and their search and reconstruction is carried out using their daughter charged particles resulting from their decay. The use of the missing mass method makes it possible to find and analyze also decays of charged short-lived particles, when one of the daughter particles is neutral and is not registered in the detector system. One of the most known examples of such decays is the decay Σ− → nπ−. In this paper, we discuss in detail the missing mass method, which was implemented as part of the KF Particle Finder package for the search and analysis of short-lived particles, and describe the use of the method in the STAR experiment (BNL, USA). The method was used to search for pion (π± → μ±ν) and kaon (K± → μ±ν and K± → π±π0) decays online on the HLT farm in the express production chain. An important feature of the express production chain in the STAR experiment is that it allows one to start calibration, production, and analysis of the data immediately after receiving them. Here, the particular features and results of the real-time application of the method within the express processing of data obtained in the BES-II program at a beam energy of 3.85 GeV/n when working with a fixed target are presented and discussed.

The paper presents an efficient Cellular Automaton based algorithm for trajectory reconstruction in the Transition Radiation Detector of the CBM experiment. The comparison of the different electron identification methods is also given.

The article is dedicated to the current state of the Geometry Database for the BM@N experiment of the NICA project. The main goal of the database is to provide a central storage of the BM@N geometries, convenient tools for managing its geometry modules, various software assembling versions of the BM@N setup as a combination of modules and additional files providing support for a set of versions. Both the Graphical User Interface (GUI) and the Application Programming Interface (API) have been developed.

Mathematical Modeling and Computational Physics 2019, MMCP 2019, High Tatra Mountains, Slovakia, 1 Jul 2019 - 5 Jul 2019; The European physical journal / Web of Conferences 226, 03005 (2020). doi:10.1051/epjconf/202022603005, Published by EDP Sciences, Les Ulis

3rd International Conference on Computing in High Energy and Nuclear Physics , CHEP 2018, Sofia, Bulgaria, 9 Jul 2018 - 13 Jul 2018; The European physical journal / Web of Conferences 214, 02030 (2019). doi:10.1051/epjconf/201921402030, This paper is dedicated to the current state of the Geometry Database (Geometry DB) for the CBM experiment. The geometry DB is an information system that supports the CBM geometry. The main aims of Geometry DB are to provide storage of the CBM geometry, convenient tools for managing the geometry modules, assembling various versions of the CBM setup as a combination of geometry modules and additional files, providing support of various versions of the CBM setup. The development is based on the analysed users’ requirements (which were formulated in User Requirements Document) and takes into account peculiarities of the workflow for simulation of particle transport through the setup. Both the Graphical User Interface (GUI) and the Application Programming Interface (API) are available for the members of the CBM collaboration., Published by EDP Sciences, Les Ulis

The Compressed Baryonic Matter (CBM) experimental setup is currently being constructed at the Facility for Antiproton and Ion Research (FAIR) acceleration complex at GSI (Darmstadt, Germany) by an international collaboration that includes a team from JINR. One of the main goals of this experiment is to study the charmonium production in high-energy nuclear collisions. The experiment will operate at extreme interaction rates of up to 10 MHz. The expected dataflow rate will be of the order of 1 TB/s, making it impossible to store all the raw data from detectors in long-term buffers. It will demand the selection of J/ψ → μ+ μ− decays in real-time. This paper presents criteria for the fast and effective selection of signal events by using exclusively data on charged muon hits collected in the Muon Chamber (MUCH) coordinate stations and describes the software implementing these criteria. The possibility of this software to solve the problem of the online selection J/ψ → μ+ μ− decays is proven.

The paper considers a problem of extrapolating functions of several variables. It is assumed that the values of the function of m variables at a finite number of points in some domain D of the m-dimensional space are given. It is required to restore the value of the function at points outside the domain D. The paper proposes a fundamentally new method for functions of several variables extrapolation. In the presented paper, the method of extrapolating a function of many variables developed by us uses the interpolation scheme of metric analysis. To solve the extrapolation problem, a scheme based on metric analysis methods is proposed. This scheme consists of two stages. In the first stage, using the metric analysis, the function is interpolated to the points of the domain D belonging to the segment of the straight line connecting the center of the domain D with the point M, in which it is necessary to restore the value of the function. In the second stage, based on the auto regression model and metric analysis, the function values are predicted along the above straight-line segment beyond the domain D up to the point M. The presented numerical example demonstrates the efficiency of the method under consideration.

In this paper, we investigate the possibility of applying various approaches to solving the problem of medium-term forecasting of daily passenger traffic volumes in the Moscow metro (MM): 1) on the basis of artificial neural networks (ANN); 2) using the singular-spectral analysis implemented in the package “Caterpillar”-SSA; 3) sharing the ANN and the “Caterpillar”-SSA approach. We demonstrate that the developed methods and algorithms allow us to conduct medium-term forecasting of passenger traffic in the MM with reasonable accuracy.

During construction in the Far North, due to the preservation of permafrost soils, the buildings are arranged on piles and foundations on the bedding soil. In the foundations of buildings for a smaller impact on the ground and prevention from defrosting of the soil, air cooling systems with cooling pipes are provided. Seasonal and daily variations in the temperature of the outside air and intensity of solar radiation cause fluctuations in the temperature regime of the upper layers of the soil. As a result of transformation of natural soils into technogenic, its physical properties change significantly when exposed to negative temperatures. Freezing of the soil thawed out over the summer and its further cooling is achieved by passing cold air in the winter through the air channels. The cooling system must provide the position of the upper surface of the frozen soil state under the building, as adopted by the project. This paper discusses the aerodynamic mode of the air cooling system for foundations on bedding in permafrost soils during the construction of various buildings and structures while preserving the base soils in a frozen state and using natural cold of the outside air, which will improve the reliability of permafrost bases. An engineering method has been developed for calculating the heat fluxes of soil and pipeline laid in thickness. A technique for engineering calculation of change in the thermal regime depending on the parameters of the outside air is given, which will make it possible to usefully use the energy of the cold enclosed in the ground to warm the outside air.

The paper describes the approaches, implemented by the authors, for the track reconstruction in data, subdivided to time slices, in the CBM experiment.

The Compressed Baryonic Matter (CBM) experiment at FAIR will play a unique role in the exploration of the QCD phase diagram in the region of high net-baryon densities, because it is designed to run at unprecedented interaction rates. High-rate operation is the key prerequisite for high-precision measurements of multi-differential observables and of rare diagnostic probes which are sensitive to the dense phase of the nuclear fireball. The goal of the CBM experiment at SIS100 (√sNN = 2-4.9 GeV) is to discover fundamental properties of QCD matter, namely, the equation-of-state at high density as it is expected to occur in the core of neutron stars, effects of chiral symmetry, and the phase structure at large baryon-chemical potentials (μB ≥ 500 MeV).We are focusing here on the contribution of JINR to the CBM experiment: design of the superconducting dipole magnet; manufacture of the straw and micro-strip silicon detectors, participation in the data taking and analysis algorithms and physics program.