Data taking has been started at the first stage of the SPASCHARM experiment on systematic study of the spin effects in strong interactions. The current setup configuration is described, and the detector characteristics attained during the beam data taking in the runs of 2018–2022 are listed.

First results on Alpha-dependence measurements in inclusive K-S(0) meson production in pi(-)Alpha interactions (Alpha=C, Al, Cu, Sn, and W) are presented at approximate to 26.5 GeV/c. The ratios of the differential cross sections of four of these nuclei to the differential cross section on aluminum were measured and the dependence of these cross sections on the atomic of the nucleus was studied. The measurements were carried out in the kinematic region of the Feynman variable 0.2 < x(F) < 0.8 and transverse momentum p(T) < 1.2 GeV/c. K-S(0) mesons were detected in the decay mode K-S(0)->pi(+)pi(-) at the SPASCHARM experimental setup using negative charged beams at beamline 14 of the U-70 accelerator complex.

First results on 𝐴-dependence measurements in inclusive K0𝑆-meson production in 兀− 𝐴-interactions (𝐴 = C, Cu, Al, Sn, W) are presented at 26.5 GeV/c. The ratios of the differential cross sections of four of these nuclei to the differential cross section on aluminum were measured and the dependence of these cross-sections on the atomic number of the nucleus was studied. The measurements were carried out in the kinematic region of the Feynman variable 0.2 < 𝐹 < 0.8 and transverse momentum 𝑝𝑇 < 1.2 GeV/c. K0𝑆-mesons were detected in the decay mode K0𝑆→ 兀+兀−-at the SPASCHARM experimental setup using negative charged beams at beamline 14 of the U-70 accelerator complex.

First results on the polarization of Λ hyperons inclusively produced on 26.5-GeV/c K^ - and π^ - beams are presented. The measurements were carried out using the SPASCHARM setup at the U-70 accelerator facility (Protvino, Russia) on nuclear targets in 2021 and 2022. The polarization of an Λ hyperon on the π^ - beam does not exceed several percent in most of the studied kinematic region. The data obtained on the K^ - -meson beam exhibit a significant positive polarization at large values of the Feynman variable xF and transverse momentum pT measured for the first time on nuclei.

First results on A -dependence measurements in inclusive K_S^0 meson production in π^-A interactions ( A=C , Al, Cu, Sn, and W) are presented at ≈26.5 GeV/c. The ratios of the differential cross sections of four of these nuclei to the differential cross section on aluminum were measured and the dependence of these cross sections on the atomic of the nucleus was studied. The measurements were carried out in the kinematic region of the Feynman variable 0.2

The DANSS detector is located directly under the nuclear reactor at the Kalinin nuclear power plant. Such a position ensures about 50 m.w.e. shielding from cosmic rays in the vertical direction; as a result, the detector occupies an intermediate position between surface and underground detectors in the shielding from cosmic rays. The sensitive volume of the detector consisting of a 1-m 3 plastic scintillator is surrounded by the multilayer passive shielding and muon veto. The main aim of the DANSS experiment is to measure the antineutrino spectrum at various distances from the source. To this end, the detector is placed on a lifting platform in order to record data at three positions of 10.9, 11.9, and 12.9 m from the reactor core. The detector can reconstruct muon tracks passing through its sensitive volume. The pressure, temperature, and decay coefficients for muons in various regions of the zenith angle θ have been determined from the muon data collected during four years using the effective generation level method.

The SPASCHARM experiment is aimed at a systematic study of the nucleon spin structure and the spin dependence of the strong interaction of antimatter and matter with matter at energies up to 45 GeV. As part of the first stage of the experiment, the study of the spin properties of hadrons will take place in a beam of negatively charged hadrons on existing beamline 14 at the operating SPASCHARM setup at the U70 facility. At the second stage, the production of polarized beams of protons and antiprotons is envisaged in beamline 24A of the U-70 accelerator facility. A polarized antiproton beam will certainly become a unique beam in the world. It is planned to measure single-spin asymmetries in dozens of reactions, both on hydrogen and on various nuclei. At the SPASCHARM facility, it is also possible to measure the transverse polarization of hyperons and elements of the spin density matrix of vector mesons. The spin structure of the nucleon will be investigated in the study of quarkonium production to determine the contribution of gluons to the proton spin. The presence of two types of polarized beams and eight types of nonpolarized beams (π ± , K ± , p , p̅ , d , C ), in combination with a polarized target, expands the range of studies of polarization phenomena and enhances the uniqueness of the project.

Detection of antineutrino by the reaction of the inverse β -decay can be used for an independent monitoring of a nuclear reactor power. DANSS detector is located directly under a commercial WWER-1000 reactor and counts up to 5000 antineutrino per day, providing the accuracy of 1.5% in 2 days of the flux measurement. A powerful system of the passive and active shielding in combination with the fine spatial segmentation of the detector allows to diminish the contribution of the background processes to a level, negligible in comparison to the statistical error. The influence of the nuclear fuel composition on the neutrino flux can be accounted for based on the input from the NPP staff.

The detection equipment of the DANSS setup includes 2500 silicon photomultipliers and approximately 100 photomultiplier tubes (PMTs). The system of data acquisition from these photosensors is based on waveform digitization, with which it is possible to simultaneously obtain both amplitude and timing information. The modules of waveform digitizers (WFDs) are made to the VME standard and allow parallel digitization of 64 differential signals at a frequency of 125 MHz with a 12-bit amplitude resolution. The programmable logic of the WFDs provides production of the system trigger based on the analysis of the PMT signals and its propagation without any additional hardware. Owing to the extremely low analog noise, it is possible to use the full dynamic range of the digitization. These WFD modules are superior to other similar modules in the throughput and may find wide application to perform similar tasks of waveform digitization.

The transverse nonuniformity of the light yield in scintillator strips of the DANSS detector was investigated on a test setup that was specially designed for this purpose using proportional chambers with a wire pitch of 1 mm. It is shown that using the approaches that were used in the DANSS experiment, the variation in the light yield due to the geometric features of the strip design is approximately 8% for a minimum ionizing particle. This study can be useful for making estimates and designing similar detectors.

The analysis of high-precision $\pi^{\pm}p \to \pi^{\pm}p$ cross section data from the EPECUR Collaboration based on the multichannel $K$-matrix approach is presented.The sharp structures seen in these data are studied in terms of both opening thresholds and new resonance contributions. Some prominent features are found to be due to the opening $K\Sigma$ channel. However, a complete description of the data is improved with the addition of two narrow resonant structures at $W\sim 1.686$ and $W\sim 1.720$ GeV. These structures are interpreted as manifestations of $S_{11}$ and $P_{11}$ resonances. The underlying nature of the observed phenomena is discussed.

Cross sections for pi+-p elastic scattering have been measured to high precision, for beam momenta between 800 and 1240 MeV/c, by the EPECUR Collaboration, using the ITEP proton synchrotron. The data precision allows comparisons of the existing partial-wave analyses (PWA) on a level not possible previously. These comparisons imply that updated PWA are required.

The EPECUR experimental setup has been designed to search for narrow resonant states by precisely measuring differential and total reaction cross sections for pion-nucleon interactions with 1-MeV pion energy steps. Over the 5 years that passed from the submission of the idea of the experiment to the start of data taking in April 2009, a non-magnetic spectrometer with a liquid hydrogen target based on the large-aperture multiwire drift chambers with a hexagonal structure has been built at the universal beamline 322 of the U-10 proton synchrotron at the Alikhanov Institute for Theoretical and Experimental Physics. Owing to the unique properties of the beamline, the beam particle momentum can be measured with an accuracy of 0.1% or better using 1-mm-pitch proportional chambers located at the first focus of the beamline. The design of numerous subsystems of the setup is based on modern electronic components including microprocessors and field programmable gate arrays. All the subsystems have been tuned and tested both individually and as parts of the whole setup. The distributed data acquisition system is based on the widely spread USB and Ethernet protocols, which help achieve high performance characteristics and take full advantage of the industrial solutions.

The EPECUR collaboration presents new high precision data on the pion-proton elastic scattering in the second resonance region. The experiment EPECUR is placed on the universal beam channel of the accelerator ITEP. The setup features 0.1% beam pion momentum tagging system, 25 cm long liquid hydrogen target, placed in mylar container and beryllium outer shell, low material wire drift chambers and high performance DAQ. More than 3 billions of triggers have been collected. The data cover pion beam momentum range 0.8 - 1.3 GeV/c and 40-120 degrees center-of-mass scattering angle range for both positive and negative pions. The measured differential cross section has 2% statistical accuracy in 2 degrees angle and 5 MeV/c momentum intervals.