Search

The study of the high-density equation of state (EOS) and the search for a possible phase transition in dense baryonic matter is the main goal of beam energy scan programs with relativistic heavy ions at energies sNN= 2–5 GeV. The most stringent constraints currently available on the high-density EOS of symmetric nuclear matter come from the present measurements of directed (v1) and elliptic flow (v2) signals of protons in Au + Au collisions. In this energy range, the anisotropic flow is strongly affected by the presence of cold spectators due to the sizable passage time. The system size dependence of anisotropic flow may help to study the participant–spectator contribution and improve our knowledge of the EOS of symmetric nuclear matter. In this work, we discuss the layout of the upgraded BM@N experiment and the anticipated performance for differential anisotropic flow measurements of identified hadrons at Nuclotron energies: sNN= 2.3–3.5 GeV.

Sections of the superconducting magnets of the SIS100 particle accelerator, under construction at the Facility for Antiproton and Ion Research (FAIR), the Society for Heavy Ion Research (GSI), Darmstadt, are going to be connected with the by-pass lines. Each line will be used to transfer a two-phase helium flow and an electric current. The electric current will be carried by four pairs of superconducting Nuclotron-type cables. Fast-ramping currents are expected to cause the generation of heat within the cables. In this work the results of a numerical thermal analysis of a bus-bar are presented. The amount of heat transferred from the environment was found based on geometric dimensions of the line and applied insulation. The amount of hysteresis loss, generated in the cable during the operation under most demanding regime of the operation of the accelerator, was calculated. According to the amount of the generated heat, the amount of the hysteresis loss is low in relation to the heat generated in the superconducting magnets. Also it was found that the cable used in the line still retains a large margin of current-carrying capacity.

The paper presents the results of physical experiments with 238U and 209Bi samples at the Nuclotron, Phasotron and LINAC-200 accelerators of the Joint Institute for Nuclear Research, with the results processed using the FLUKA, GEANT4 and MCNP programs.

The anisotropic flow is one of the important observables sensitive to the equation of state (EOS) and transport properties of the strongly interacting matter created in relativistic heavy-ion collisions. In this work, we report a detailed multi-differential study of the directed (v1), elliptic (v2), triangular (v3), and quadrangular (v4) flow coefficients of protons in relativistic heavy-ion collisions at sNN = 2.2–4.5 GeV using several hadronic transport models. Recent published results for Au + Au collisions at sNN = 2.4 GeV from HADES experiment and at sNN = 3.0 GeV from the STAR experiment have been used for comparison. The study motivates further experimental investigations of the anisotropic collective flow of protons and neutrons in a high baryon density region.

NICA is an international project accelerator collider complex under construction at the Joint Institute for Nuclear Research in Dubna. The facility is aimed at providing collider experiments with heavy ions up to gold in the center of mass energy from 4 to 11 GeV/u and an average luminosity up to 1 $\times\, 10^{27}$ cm $^\mathbf {-2}$ s $^\mathbf {-1}$ for Au $^{79+}$ . Collision experiments with polarized deuterons and protons are also foreseen. The facility includes two injector chains, a new superconducting booster synchrotron, the existing 6 AGeV superconducting synchrotron Nuclotron, and a new superconducting collider consisting of two rings, each 503 m in circumference. The planned FAIR synchrotron SIS100 has to deliver high-intensity beams for the FAIR project at GSI, Darmstadt. This machine will use fast-cycling 4 T/s magnets with a magnetic field up to 2 T. The NICA booster synchrotron, the NICA collider, and the heavy ion synchrotron SIS100 are based on iron-dominated window frame-type magnets with a hollow superconductor winding analogous to the Nuclotron magnet. Progress in the manufacturing and testing of the NICA magnets and the SIS100 superconducting magnets is presented.

BM@N (Baryonic Matter at Nuclotron) is the first experiment undertaken at the accelerator complex of NICA-Nuclotron. The aim of the BM@N experiment is to study interactions of relativistic heavy ion beams with fixed targets. The scientific program of the BM@N experiment comprises studies of nuclear matter in the intermediate energy range between experiments at the SIS and NICA/FAIR facilities. The BM@N experiment has recorded first experimental data in December 2016. The experimental runs were performed in the deuteron and carbon beams of kinetic energy per nucleon ranging from 3.5 to 4.5 GeV. The extended configuration of the BM@N set-up was realized in recent runs with the argon and krypton beams. The first measurement of short range correlations of nucleons in carbon nucleus was performed in inverse kinematics with the carbon beam and liquid hydrogen target. The experimental program covering physics of heavy ion collisions as well as first experimental results on the production of hyperons are presented.

We consider the capability of flexible spin-transparent polarization control and manipulation in conventional synchrotrons at integer spin resonances by means of spin navigators. The latter are designed as a couple of small solenoids separated by a constant beam bend. We formulate the requirements to the navigator design considering the criteria for stability of the spin motion in the presence of synchrotron energy oscillations. We propose the design of a novel spin-flipping system free of resonant beam depolarization based on such a spin navigator. We discuss the possibilities of testing spin-flipping systems at an integer spin resonance with protons in the Nuclotron ring at JINR in Dubna, Russia, and with deuterons in the RHIC rings at BNL in Upton, New York. The results are relevant to the existing and future facilities where the spin transparency mode can be applied for polarization control.

Universe 7(6), 171 - (2021). doi:10.3390/universe7060171, Published by MDPI, Basel

The differential cross sections of the charge exchange reaction $$dp \rightarrow (pp)n$$ has been measured at 1.75 GeV/c per nucleon for small transferred momenta using the one arm magnetic spectrometer STRELA at the Nuclotron accelerator in JINR Dubna. The ratio of the differential cross section of the charge exchange reaction $$dp \rightarrow (pp)n$$ to that of the $$np \rightarrow pn$$ elementary process is discussed in order to estimate the spin-dependent part of the $$np \rightarrow pn$$ charge exchange amplitude. The $$np \rightarrow pn$$ amplitude turned out to be predominantly spin-dependent.

A precision hybrid magnetic three-arm «SCAN-3» spectrometer is being developed at the Joint Institute for Nuclear Research. The spectrometer is designed to detect charged particles (π±, K±, p) and neutrons produced in the target by collisions of the NUCLOTRON high-interactive beam particles with target nuclei. One of the tasks of the spectrometer is to detect neutrons from the decay of the η-meson nucleus via nπ- and pn- channels. To complete this task, two arms of the spectrometer will be created that consist of six multilayer neutron detectors based on scintillation blocks. The characteristics of a neutron detector that consists of five scintillation blocks are considered. The detector was studied using the cosmic rays and the neutron beam produced by the stripping reaction of the NUCLOTRON extracted deuteron beam on a fixed target.

Serial production of superconducting (SC) magnets for the Nuclotron Ion-based fAcility (NICA) and Facility for Antiproton and Ion Research (FAIR) projects is currently underway at the Joint Institute for Nuclear Research (JINR) in Dubna, Russia [1]. SC-coil electrical parameters should be checked before each stage of assembling and cryogenic testing to avoid faults, such as inter-turn short circuit and insulation failure. A system for checking of SC-magnets electrical parameters is described in this paper. The results obtained by this system are presented and outlined.

The aim of the deuteron spin structure (DSS) experiment is to obtain polarization observables in dp elastic scattering and in dp breakup at large CMS angles (> 60°). The dp breakup reaction has been investigated by the scintillation detectors placed at the vicinity of the Internal Target Station (ITS) of Nuclotron. Calibration data have been obtained at the deuteron energy of 300 - 500 MeV. The main goal of this report is to present the calibration procedure of the ΔE - E detectors. Calibration coefficients are used to recover the deposited particle energy.

Properties of spectator matter created in central (of 0-5% centrality) 197Au– 197Au and 208Pb– 208Pb collisions with energies typical for the Nuclotron based Ion Collider fAcility (NICA) accelerator complex are calculated with a recently developed Abrasion-Ablation Monte Carlo for Colliders (AAMCC) model. The sensitivity of cross-sections of emission of spectator neutrons to the nuclear deformation of 197Au and to the presence of neutron skin in 208Pb is demonstrated. The influence of the nuclear deformation of the 197Au on the forward-backward asymmetry of free spectator nucleons and on the asymmetry of the total volume of spectator matter is investigated.

The paper presents measurements of the noise characteristics of silicon photomultipliers in the temperature range from 27.7 °C to 39.1 °C, as well as study of the response of the detector prototypes with Ketek and Hamamatsu SiPM readout to the light source at different voltages. The prototype with SiPM readout from Ketek was tested at the Joint Institute for Nuclear Research Nuclotron deuteron beam at the energy of 4 GeV/nucleon. Time resolution and amplitude of the signal have been estimated.

Analyzing power in elastic proton-proton scattering was obtained at the Nuclotron Internal Target Station using a polarized deuteron beam and a polyethylene target. The selection of useful events was performed using the time and amplitude information from scintillation counters. The asymmetry on hydrogen was obtained by the subtraction of the carbon background. The obtained analyzing power values are compared with the predictions of the partial-wave analysis SAID at the beam energies of 500 and 650 MeV/nucleon.

The the polarimeter upgrade program at the Nuclotron internal target is presented. This polarimeter is intended for polarization experiments to study of the spin structure of two- and three-nucleon systems. The simulation of the pd-elastic and pp-elastic scattering for 500 - 1000 MeV proton energy to optimize the experimental setup and the first test of new detectors are performed.

The Forward Hadron Calorimeter (FHCal) is one of the sub-detectors of MPD/NICA (Nuclotron-based Ion Collider fAcility). FHCal consists of two arms, each containing 44 modules. Modules have longitudinal segmentation and are divided into 7 equal sections. Each section contains 6 pairs of lead-scintillator plates. FHCal’s main goal is to determine geometry of ion collision by measuring the energy distribution of spectators. In order to determine the energy distribution in FHCal, modules were calibrated with cosmic muons. Another important goal facing FHCal is determination of ion collision point in MPD during first stage of MPD’s operation, when no precise ways of doing this will be available. Two methods are presented in this work: using energy distribution in FHCal and using difference in time pulses from opposite FHCal arms.

Within the framework of the Nuclotron–based Ion Collider fAcility (NICA) project an Innovation Block is being constructed. It includes an applied research station for microchips with a package for radiation resistance testing. The ions up to Au with the energy range of 150-350 MeV/n are available for researches. The detailed overview of a technical station for irradiation by long-range ions is presented. A concept for reconstruction of the capsulated microchip structure at it’s interaction with high-energy ions was proposed.

The Baryonic Matter at Nuclotron (BM@N) is the first experiment with a fixed target at the Nuclotron-based Ion Collider fAcility (NICA) in Dubna (Russia). Along with baryonic matter study, the BM@N physics program includes the study of Short-Range Correlations (SRC) in nuclei. The SRC measurement was carried out in 2018. We used 12C beam with the momentum of 48 GeV/c and a liquid hydrogen target. The quasi-free scattering of 12C on protons was recorded with the BM@N spectrometer, which was slightly modified for the SRC experiment. Particularly, the target proton and knocked out proton under the condition of scattering at 90 degrees in the center-of-mass coordinate system were recorded in the arm spectrometer using time-of-flight and coordinate detectors. After interaction, the residual nucleus continued moving along the beam and passed through the scintillator and coordinate detectors as well as the analyzing magnet. This contribution describes the track reconstruction in Multiwire Proportional Chambers (MWPC) and Silicon Detector systems (Si), as well as a method of obtaining combined tracks after the target using the information from MWPC and Si. This is a basis for the identification of nuclear fragments described in the first physics analysis, which was submitted for publication.

We present a concept for control of the ion polarization, called a transparent spin method. The spin transparency is achieved by designing such a synchrotron structure that the net spin rotation angle in one particle turn is zero. The polarization direction of any ions including deuterons can be efficiently controlled using weak quasistatic fields. These fields allow for dynamic adjustment of the polarization direction during an experiment. The main features of the transparent spin method are illustrated in a figure-eight collider. The results are relevant to the electron-ion collider considered in the U.S., the nuclotron-based ion collider facility constructed in Russia, and a polarized electron-ion collider planned in China.

Deuteron spin structure program is aimed on extraction of two and three nucleon forces information, including their spin dependent parts, from dp elastic and dp breakup processes investigated at intermediate energies. The dp elastic data were obtained at Internal Target Station of Nuclotron (JINR) in the energy range 400-1800 MeV using polarized deuteron beam. Strong sensitivity to the short range spin structure of the isoscalar nucleon-nucleon correlations is observed in deuteron analyzing powers. Preliminary results of the the cross section for the dp breakup reaction have been obtained at 400 MeV of deuteron energy.

Time evolution of shear viscosity $\ensuremath{\eta}$, entropy density $s$, and their ratio $\ensuremath{\eta}/s$ in the central area of central gold-gold collisions at energies available at the Nuclotron-based Ion Collider fAcility (NICA) are studied within the ultrarelativistic quantum molecular dynamics (UrQMD) transport model. The extracted values of energy density, net baryon density, and net strangeness density are used as input to (i) the statistical model of an ideal hadron gas to define temperature, baryochemical potential, and strangeness chemical potential, and to (ii) a UrQMD box with periodic boundary conditions to study the relaxation process of highly excited matter. During the relaxation stage, the shear viscosity is determined in the framework of the Green-Kubo approach. The procedure is performed for each of 20 time slices, corresponding to conditions in the central area of the fireball at times from 1 to $20\mathrm{fm}/c$. For all tested energies the ratio $\ensuremath{\eta}/s$ reaches its minimum, ${\left(\ensuremath{\eta}/s\right)}_{\mathrm{min}}\ensuremath{\approx}0.3$ at $t\ensuremath{\approx}5\phantom{\rule{4pt}{0ex}}\mathrm{fm}/c$. Then it increases up to the late stages of the system evolution. This rise is accompanied by the drop of both temperature and strangeness chemical potential and by the increase of baryochemical potential.

A new generation of experiments on relativistic nuclear physics is planned to be started in the nearest years at the Nuclotron-based Ion Collider facility (NICA) under construction at the Joint Institute for Nuclear Research in Dubna. The fixed target experiment BM@N (Baryonic Matter at Nuclotron) is considered as a first stage towards the implementation of the physics program available at NICA. For a successful accomplishment of the BM@N physics program, a well-developed and tested software package for simulation, digitization, reconstruction and analysis of collision events and other supporting tasks is of utmost importance. The data flow scheme of the experiment is shown. Offine and online software systems, such as the main BmnRoot framework, databases of the experiment, data monitoring and others providing information support for the experiment are presented. The implementation of the software systems is a necessary stage for the successful operation of the BM@N experiment.

Over 30 years there has been no comprehensive understanding of the mechanism of soft photons (energy smaller than 50 MeV) formation. Experimental data indicate an excess of their yield in hadron and nuclear interactions in comparison with calculations performed in QED. For a more thorough study of this phenomenon at the Nuclotron (a superconducting accelerator in JINR), preliminary measurements have been carried out with using an electromagnetic calorimeter based on BGO crystals. These results are consistent with the world data. In JINR, in connection with the building of a future accelerator complex NICA, it has become possible to carry out such studies in pp, pA and AA interactions at energies up to 25 A GeV. Our group develops the conception of an heterogeneous electromagnetic calorimeter as “spaghetti” and “shashlik” types based on gadolinium gallium garnet (GaGG) crystals with a low threshold for registration of photons. The first tests of prototypes of them manufactured at JINR on the basis of the GaGG and a mixture of tungstate and copper as an absorber are reported.

The Nuclotron-based Ion Collider fAcility (NICA) accelerator complex is scheduled to be put into operation in full configuration in 2023 at JINR. This facility comprising the existing Nuclotron together with two newly created superconducting accelerators-booster and collider-will require additional refrigerating capacity at 4.5 and 77 K. The helium cryogenic system of the NICA complex will be constructed as a result of the modernization of the existing equipment for cryogenic supply of the Nuclotron, but the liquid nitrogen plant will be completely new. It will be based on a 1300 kg/h nitrogen liquefier and two 500 kg/h recondensers of nitrogen vapors. This report describes the schematic diagram of the system of liquid nitrogen that will be used for refrigerating the thermally insulating shields of the cryostats at 77 K and at the first stage of cooling down three accelerator rings with the total length of about 1 km and the “cold” mass of 290 t. We demonstrate the status and recent development of the nitrogen cryogenic system: location, basic parameters, and design of major components and discuss their phased commissioning.

Nuclotron-based ion collider facility (NICA) is an international project-accelerator collider complex under construction at the Joint Institute for Nuclear Research in Dubna. The facility is aimed at providing collider experiments with heavy ions up to gold in the center of mass energy from 4 to 11 GeV/u and an average luminosity up to 1·1027 cm−2·s−1 for Au79+. Collision experiments with polarized deuterons and protons are also foreseen. The facility includes two injector chains, a new superconducting booster synchrotron, the existing 6 AGeV superconducting synchrotron Nuclotron, and a new superconducting collider consisting of two rings, each 503 m in circumference. The planned FAIR synchrotron SIS100 has to deliver high intensity beams for the FAIR project at GSI, Darmstadt. This machine will use fast-cycling 4 T/s magnets with a magnetic field up to 2 T. The NICA booster synchrotron, the NICA collider, and the heavy ion synchrotron SIS100 are based on iron-dominated “window frame”—type magnets with a hollow superconductor winding analogous to the Nuclotron magnet. The status on the manufacturing and testing of the NICA magnets and the SIS100 superconducting quadrupole and corrector magnets are discussed.

Nuclotron-based Ion Collider fAсility (NICA) is a new accelerator collider complex currently under construction at the Joint Institute for Nuclear Research (JINR) in Dubna, Russia. The facility includes a new superconducting booster synchrotron whose layout includes 40 dipole and 48 quadrupole superferric magnets. Booster magnets are under serial production, assembling and testing at the new test facility at JINR, Dubna. The designs of NICA magnets are based on the Nuclotron magnet design. The dipole magnets for the NICA booster have a length of 2.14 m, an aperture of 128/165 mm, and a curved yoke with bending radius of 14.1 m. Two quadrupole magnets are connected together to form a doublet. Measurement of the magnetic field parameters are assumed for each booster magnet. 80% of the dipole magnets and 10% of the doublets have successfully passed the tests. We present the cold test results that were obtained from the magnetic measurements of dipole magnets and compare them with the requirements of the specification. Preliminary results of cold magnetic measurements of the first serial doublets are summarized here.

Experimental and theoretical studies of fluctuations in nucleus-nucleus interactions at high energies have started to play a major role in understanding of the concept of strong interactions. The elaborated procedures have been developed to disentangle different processes happening during nucleus-nucleus collisions. The fluctuations caused by a variation of the number of nucleons which participated in a collision are frequently considered the unwanted one. The methods to reduce the impact of these fluctuations in fixed-target experiments are reviewed and tested. They can be of key importance in the following ongoing fixed-target heavy-ion experiments: NA61/SHINE at the CERN SPS, STAR-FXT at the BNL RHIC, BMN at JINR Nuclotron, HADES at the GSI SIS18 and in future experiments such as NA60+ at the CERN SPS, CBM at the FAIR SIS100, JHITS at J-PARC-HI MR.

The project NICA (Nuclotron-based Ion Collider fAcility) is aimed to study hot and baryon rich QCD matter in heavy ion collisions in the energy range up to s NN = 11 GeV . The heavy ion program includes a study of collective phenomena, dilepton, hyperon and hypernuclei production under extreme conditions of highest baryonic density. This program will be performed at a fixed target experiment BM@N and with MPD detector at the NICA collider.

In the 1990s, for Nuclotron, the pioneer accelerator using fast ramped superconducting magnets, a novel cable with superconducting strands wrapped around a cooling tube was developed. Such cable fabrication technology was advanced and adopted for the SIS100 or NICA project. In parallel with major application for fast ramped superferric magnets, application for high field magnets with a cosine-theta type is investigated. In this paper, we give an overview of the history of Nuclotron-type cables, list its advantages, and outline its applicability far beyond the original usage field.

The performance of several trigger counters based on plastic scintillators with silicon photomultiplier readout is investigated with cosmic rays. Efficiency and time resolution are measured using digital waveform analysis. The obtained results are relevant for trigger subsystems of Multi-Purpose Detector (MPD) and Baryonic Matter at the Nuclotron (BM@N) at the NICA heavy-ion collider. The results show very high efficiency and good timing performance of the counters.

The Nuclotron at the Joint Institute for Nuclear Research in Dubna can deliver gold beams with kinetic energies between 2 and 4.5 A GeV. In heavy-ion collisions at these energies, it is expected that the nuclear fireball will be compressed by up to approximately four times the saturation density. This offers the opportunity to study the high-density equation-of-state (EOS) of nuclear matter in the laboratory, which is needed for our understanding of the structure of neutron stars and the dynamics of neutron star mergers. The Baryonic Matter at the Nuclotron (BM@N) experiment will be upgraded to perform multi-differential measurements of hadrons including (multi-) strange hyperons, which are promising probes of the high-density EOS, and of new phases of quantum chromodynamic (QCD) matter. The layout of the upgraded BM@N experiment and the results of feasibility studies are presented.

The NICA (Nuclotron-based Ion Collider fAcility) project is under realization at the Joint Institute for Nuclear Research (JINR, Dubna). The main goal of the project is an experimental study of hot and dense strongly interacting matter in heavy ion (up to Au) collisions at center-of-mass energies up to 11 GeV per nucleon. The physics program will be performed at two experiments, BM@N (Baryonic Matter at Nuclotron) at beams extracted from the Nuclotron, and MPD (Multi-Purpose Detector) at the NICA collider. The aim of the BM@N experiment is to study interactions of relativistic heavy ion beams with fixed targets. The scientific program comprises studies of nuclear matter in the intermediate energy range between experiments at the SIS and NICA/FAIR facilities. The BM@N experiment has recorded first experimental data in the carbon, argon and krypton beams of kinetic energy per nucleon ranging from 2.3 to 4.5 GeV per nucleon. The first measurement of short range correlations of nucleons in carbon nucleus was performed in inverse kinematics with the carbon beam and liquid hydrogen target. The MPD detector is under construction to study hot and baryon rich QCD matter in heavy ion collisions at the NICA collider in the energy range $\sqrt{s_{NN}} = 4 \div 11$ GeV. Physics program includes the study of collective phenomena, $\Lambda$ polarization, dilepton, hyperon and hypernuclei production under extreme conditions of highest baryonic density.

The analyzing powers for neutron charge exchange nA → pX reactions on nuclei have been measured on C, CH2 and Cu targets at incident neutron momenta 3.0 - 4.2 GeV/c by detecting one charged particle in forward direction. The polarized neutron measurements are the first of their kind. The experiment was performed using the Nuclotron accelerator in JINR Dubna, where polarized neutrons and protons were obtained from breakup of a polarized deuteron beam which has a maximum momentum of 13 GeV/c. The polarimeter ALPOM2 was used to obtain the analyzing power dependence on the transverse momentum of the final-state nucleon. These data have been used to estimate the figure of merit of a proposed experiment at Jefferson Laboratory to measure the recoiling neutron polarization in the quasi-elastic 2 H(e, e′n) reaction, which yields information on the charge and magnetic elastic form factors of the neutron.

The paper describes the JINR polarized ion source operating by means of the atomic beam method. The latest results of the SPI testing are presented. Polarized and unpolarized deuteron beams as well as the polarized proton beam were produced to accelerate in the NUCLOTRON. The conceptual design of a new universal low energy polarimeter at NUCLOTRON is also presented. It is proposed to install a new polarimeter behind the linear accelerator. The 3He target of this setup allows one to carry out measuring both the vector polarization of protons and vector and tensor polarization of deuterons. It is assumed that the new design of the polarimeter will make it possible to measure vector and tensor polarization of deuterons at the same time. Fabrication of the basic parts of the modern polarimeter is in progress now.

The NICA (Nuclotron-based Ion Collider fAcility) is the new international research facility under construction at the Joint Institute for Nuclear Research (JINR) in Dubna. The main targets of the facility are the following: 1) study of hot and dense baryonic matter at the energy range of the maximum baryonic density; 2) investigation of nucleon spin structure and polarization phenomena; 3) development of JINR accelerator facility for high energy physics research based on the new collider of relativistic ions from protons to gold and polarized protons and deuterons as well with the maximum collision energy of sqrt(sNN) ~11GeV (Au79+ +Au79+) and ~ 27 GeV (p+p). An average luminosity of the collider is expected at the level of 1027 cm-2 s-1 for Au (79+) and 1032 cm-2 s-1 for polarized protons at 27 GeV. Two collider detector setups MPD and SPD are under design and construction. The setup BM@N (Baryonic Matter at Nuclotron) was commissioned for data taken at the existing Nuclotron beam fixed target area. The MPD construction process is progressing well. The essential step to the SPD project was made in 2018.

BM@N (Baryonic Matter at the Nuclotron) is a fixed target experiment aimed to study nuclear matter in the relativistic heavy-ion collisions at the Nuclotron accelerator in JINR. The BM@N tracking system is based on Gas Electron Multipliers (GEM) detectors mounted inside the BM@N analyzing magnet. The Cathode Strip Chamber (CSC) is installed outside the magnet. The CSC is used for improvement of particles momentum identification. The structure of the GEM detectors and the CSC prototype and the results of study of their characteristics are presented. The GEM detectors and CSC are integrated into the BM@N experimental setup and data acquisition system. The results of first tests of the GEM tracking system and CSC in last runs are shortly reviewed.

BM@N (Baryonic Matter at Nuclotron) is the first experiment to be realized at the accelerator complex of NICA-Nuclotron at JINR (Dubna). The aim of the experiment is to study interactions of relativistic heavy ion beams of kinetic energy per nucleon ranging from 1 to 4.5 GeV with fixed targets. First results of the analysis of minimum bias interactions of the deuteron and carbon beams of 4 AGeV kinetic energy with different targets are discussed. Preliminary results from the data collected in the recent experimental run with the argon beam are also presented.

The current deuteron beam polarimetry at the Nuclotron is provided by the Internal Target polarimeter based on the use of the asymmetry in dpelastic scattering at large angles in the cms at 270 MeV. The upgraded deuteron beam polarimeter has been used to obtain the vector and tensor polarizations during 2016/2017 runs for the DSS experimental program. The polarimeter has been also used to tune the polarized ion source parameters for 6 different spin modes. The data analysis has been performed using the developed software based on C++ language and ROOT5 library

The vector Ay and tensor analyzing powers Ayy and Axx for dp-elastic scattering were measured at the energy of 800 MeV and at the angular range from 60° to 135° in the center-of-mass system at the JINR Nuclotron. The experimental data are compared with the calculations obtained within framework of relativistic multiple scattering approach.

The superconducting synchrotron Nuclotron [1] is the one of the main parts of the NICA/MPD project [2] in the Laboratory of High Energy Physics of JINR in Dubna. During the work on updating the Nuclotron control and monitoring systems the new injection beam profiles measurement system was developed, produced and successfully put into operation. The development process and operation results are described.

The main detector system at the Nuclotron-based Ion Collider fAcility (NICA) located in Dubna, Russia is the Multi-Purpose Detector (MPD). For better calibration reason, the MPD needs an additional trigger system for an off-beam calibration of MPD sub-detectors and for rejection (veto) of cosmic muons. The system should also be useful for practical astrophysics observations of cosmic showers. The consortium NICA-PL group defines goals and basic assumptions for the MPD Cosmic Ray Detector (MCORD). This article describes the conceptual design and simulation plans of the MCORD detector based on plastic scintillators with SiPM photodetectors and electronic digital system based on the MicroTCA crate.

η-mesic nucleus or the quasibound nuclear state of an η-meson in a nucleus is caused by the strong-interaction force alone. The project SCAN2 is aimed at searching and studying the η-meson nuclei production. The experiment is based on two-arms spectrometer using internal target at the Nuclotron. The setup was designed to study products from η-meson nucleus decay in the reaction d + 12C → (A)η + X → π + p + (A – 2) at deuteron energies from 0:5 to 2:5 GeV/nucl. The energy spectrum of secondary protons has been measured. The dependence of the yields of protons and pions on the beam energy has been obtained. This dependence can show us the minimum energy for the S 11 resonance formation. The first prototype of the neutron detector, which will be used in a new modified experimental setup SCAN3 for recording of neutrons from η-nucleus decays in the πn and pn channels, has been tested. The time-offlight method to obtain the neutron spectrum was used. The time resolution and efficiency of the neutron detector have been obtained.