P.B. Kravchenko

  (HEPD PNPI)

Search for Muon Catalyzed d+3He Fusion.
  Abstract:
This report presents the results of an experiment (PSI, Switzerland) aimed at observation of the muon catalyzed d+3He fusion reaction which might occur after a negative muon stop in the D2+3He (HD+3He) gas mixture. The basic element of the experimental setup is a Time Projection Chamber (TPC), operated 31 K temperature, which can detect the incoming muons and the products of the fusion reaction.

O.B.~Samoylov

  (DLNP JINR, Dubna)

Decade work results from the NOvA experiment.
  (Presentation)
  Video
  Abstract:
The NOvA (NuMI Off-Axis Electron Neutrino Appearance) experiment is a long-baseline neutrino experiment designed to study neutrino oscillations and fundamental neutrino properties. NOvA is located at Fermilab in Illinois and consists of two identical highly-segmented liquid scintillator detectors: the Near Detector, situated near the neutrino source at NuMI (Neutrinos at the Main Injector) beam complex, and the Far Detector, located about 810 km away in Minnesota. By comparing the neutrino interactions in these two detectors, NOvA can observe neutrino oscillations over a long baseline, which enables investigation into several key questions, including neutrino mass hierarchy, CP-violation in the lepton sector, and neutrino oscillation parameters. NOvA also provides data for understanding neutrino interactions with matter, measuring neutrino cross-section, and searches for exotic phenomena such as sterile neutrinos, dark matter, magnetic monopoles and allows monitoring signals from space and atmosphere, for example, supernova neutrinos, gravitational waves, atmospheric neutrinos and muons. In this talk we summarise decade work results from the NOvA experiment and outline plans for the future.

Shaginyan V.R.

  (TD of PNPI NRC KI)

Violation of time reversal and baryon symmetry.
  (Presentation)
  Video
  Abstract:
We discuss two phenomena: asymmetric conductivity in solids with strongly correlated fermions and baryon asymmetry in the Universe. Effective theories of gravity, even their quantum versions, cannot explain baryon asymmetry, the existence of the arrow of time, and the high entropy of the Universe.

Derbin A.V.

  (NRD, PNPI NRC KI)

Experimental searches for solar axions.
  (Presentation)
  Video
  Abstract:
Axions solve the strong CP-problem and are well-motivated candidates for the role of dark matter particles. The expected fluxes and spectra of solar axions, the basic reactions of the production and detections of axions, and the main results of the search for axions and axion-like particles are presented. Experiments on the conversion of solar axions into photons in a laboratory magnetic field, the resonant absorption of solar axions by atomic nuclei, and the axioelectric effect in atoms are discussed in more detail.

Yubing Dong

  (IHEP CAS, Bejing)

Hadronic exotics: molecular and compact scenarios.
  (Presentation)
  Video
  Abstract:
A short review on the hadron exotics of XYZ particles is given. Those new structures are near threshold with narrow widths and contain heavy flavor. Then, the molecular scenario, in the hadronic degrees of freedom, is employed to understand their decay properties. Finally, the new observed non-strange hexaquark state is discussed as well. It is far from threshold with small width and it is expected to be compact in the framework of quark degrees of freedom.

Mitropolsky I. A.

  (NRD, PNPI NRC KI)

DATABASE AND SYSTEMATICS OF MAGNETIC MOMENTS OF THE NUCLEAR GROUND STATES.
  (Presentation)
  Video
  Abstract:
In the work, the magnetic moments of the ground states of atomic nuclei are studied without the involvement of artificial intelligence. A database of properties of all nuclear states with experimentally determined magnetic moments has been created for further study and analysis. At the first stage, the systematics of nuclear magnetic moments was carried out both in magnitude and in mass number A, charge Z, number of neutrons N and the spin of the nuclear state. On the basis of a single-particle model, the magnetic moments of the ground states of all A-odd nuclei are systematized. The magnetic moments of light and near-magical A-odd nuclei are described on the basis of a single-particle model with spherical symmetry. The configurations, spins, and magnetic moments of the ground states of odd-odd nuclei are estimated based on the model of independent particles. Two methods for calculating the magnetic moments of odd-odd nuclei are proposed: using single-particle calculated values or using experimental values in neighboring A-odd nuclei. The quadrupole deformation shifts the magnetic moments of the A-odd nuclei to the region between the limit values corresponding to the spherical symmetry of the nucleus. This qualitative observation is confirmed by shell calculations of magnetic moments.

Andrey Ye. Shevel

  (HEPD, PNPI NRC KI)

Machine Learning prototype platform.
  (Presentation)
  Video
  Abstract:
It is planned to describe the use of machine learning (ML) technology for data analysis in High Energy Physics. Briefly outline the contributions of the 2024 Nobel laureates to physics research. The contemporary development of large language models using artificial neural networks is reviewed. The technical features of the developed platform are described, as well as arguments in favor of the effectiveness of using the platform for developers. The platform is developed using a language model of a special architecture "Retrieval Augmented Generation". The presentation claims that such platforms will become an integral part of every development in the foreseeable future. A demonstration of the real functioning of the platform is planned.

B.I. Ermolaev

  (A.I. Ioffe PTI RAS)

Present state of the proton spin problem.
  (Presentation)
  Video
  Abstract:
Proton is a composite particle, so its spin (= 1/2) is expected to be the sum of spins of the constituents of the proton. However, European Muon Collaboration stated in 1988 that there is a big discrepancy between the proton spin and the sum of spins of the partons (quarks and gluons). This result was so unexpected that it was named Proton Spin Puzzle aka Proton Spin Crisis. I discuss the present state of this problem and ways to solve it.

Solovyev D.A.

  (PNPI NRC KI)

Nonresonant effects in precision atomic spectroscopy.
  (Presentation)
  Video

A.P. Serebrov

  (PNPI NRC KI)

Analysis of experimental data on neutron decay for the possibility of the existence of the right vector boson 𝑾_𝑹.
  (Presentation)
  Video
  Abstract:
The analysis of the latest most accurate experimental data on neutron decay for the possibility of the existence of the right vector boson 𝑾_𝑹 was carried out. As the result of the analysis, it was found that there is an indication of the existence of the right vector boson 𝑾_𝑹 with a mass of 𝑀_𝑾𝑹 = 304± ²⁸₂₂ GeV and a mixing angle with 𝑊_𝐿: 𝜁 = −0.038 ± 0.014. This result should be considered, on the one hand, as a challenge to experimental physics at colliders, where the lower limit on the mass of the right vector boson 𝑾_𝑹 is significantly higher, and on the other hand, it indicates the need for even more accurate measurements of neutron decay and its theoretical analysis. Possible consequences are considered, assuming that the result can be confirmed. First, an extension of the Standard Model by introducing right vector bosons 𝑾_𝑹^±, 𝑍_𝑹 and right neutrinos would be required. Second, right neutrinos can be considered as candidates for dark matter.

I.B. Smirnov

  (HEPD, PNPI NRC KI)

Reconstruction of spatial resolution of multilayer position-sensitive detectors.
  (Presentation
  Video
  Abstract:
Mathematical methods for reconstructing the spatial resolution inherent to position-sensitive detectors of fast charged particles are considered. The resolution is reconstructed from experimental data. The methods should be used for detectors consisting of a small number of detecting layers without reference detectors. The assumption of similarity of layers is not used. The proposed method allows the user to obtain either the individual resolution of each layer or the mean squared resolutions of all layers or their combinations, when the individual resolutions cannot be obtained.

M.G. Ryskin

  (PNPI NRC KI)

Multiplicity distributions in the eikonal and the U -matrix unitarization schemes.
  (Presentation)
  Video
  Abstract:
The multiplicity distribution of charged particles produced in the central rapidity (|η| < 2.5) region is calculated for the eikonal and the U -matrix unitarization schemes using the AGK cutting rules and compared with the ATLAS 13 TeV data. The data favours the eikonal approach.

Murin Yu. A.

  (LHEP JINR, Dubna) for the NICA MPD ITS Consortium

The NICA MPD ITS project current status and perspectives.
  Abstract:
Current status, bottlenecks and ways undertaken to overcome them will be reviewed for all work packages of the NICA MPD MAPS vertex detector project managed as joint effort of Russian and Chinese teams united under the name of the NICA MPD ITS Consortium.

I.V. Voronchikhin

  (Tomsk Polytechnic University)

Productuon of dark matter mediators at fixed target experiments.
  (Presentation)
  Video
  Abstract:
We derive the bounds on dark matter parameter space from the absence of the signal events on dark matter spin-0 and spin-2 mediators in the electron beam fixed target experiments. We also discuss the impact of atomic form-factor parametrization on the total production cross-section of the mediators. The resonant productions of mediators are discussed for the annihilation of electrons on thesecondary positrons of the electromagnetic shower. For the lepton-specific scalar mediator the thermal target curves are derived for scalar, Majorana, Dirac and vector dark matter.
(based on the PhD thesis).

Arutyunova A.Yu.

  (HEPD, PNPI NRC KI)

Preparation of an experiment "Compton scattering from hydrogen and helium nuclei using an active target".
  (Presentation)
  Abstract:
The results of the work aimed at preparing for the Compton scattering experiment from hydrogen and helium to obtain the value of the polarizability of nucleons will be presented. Compton scattering studies are supposed to be performed using active targets (ACTAF2, COMPTON ionization chambers). The errors of measuring the polarizabilities of the proton were analyzed, as well as the study and calibration of electronics were performed. Using an active target (ACTAF2), electron drift velocities in various gases – Ar, He, He+5%N2, energy spectra of alpha particles (Am-241) were measured, the energy of electron-ion pair formation was determined and the energy scale was calibrated.

Larionov V.E.

  (HEPD, PNPI)

Polarized gas targets within the framework of a project studying nuclear fusion at energies up to 100 keV.
  (Presentation)
  Abstract:
The present work is dedicated to the development and optimization of a polarized atomic beam source. This work is carried out within the framework of the nuclear-physical experiment PolFusion, which aims to study fusion reactions 2H (d, p) 3H and 2H (d, n) 3He with polarization of the initial particles in the low-energy range up to 100 keV.
    The work includes the following stages: the development of a dissociator and a beam formation system, modeling of the polarizer using the Monte Carlo method, and the optimization of the polarized atomic beam source.

Rozhdestvensky A. Yu.

  (HEPD, PNPI)

Development of a system of scintillation detectors for space radiation suppression in the experiment aims to study dd-fusion reactions with the low beam energy (PolFusion).
  (Presentation)
  Abstract:
Work will be presented on the development of a system of scintillation detectors for space radiation suppression in the experiment aims to study dd-fusion reactions with the low beam energy (PolFusion).
     The work includes the following stages: modeling of the central detector system of the PolFusion experiment and the scintillation detector system, development of the design of the scintillation detector system and the results of test measurements of cosmic radiation.

Burmasov N.A.

  (HEPD, PNPI)

Coherent vector meson photoproduction and dimuon continuum production with the ALICE experiment at the LHC.
  (Presentation)
  Abstract:
Ultraperipheral collisions of heavy ions provide a unique opportunity for analysis of two-photon and photonuclear interactions in a clean environment, with hadronic interactions being supressed. Coherent vector meson production is of particular interest, as it can be used to probe nuclear parton density functions at very low Bjorken-x. In addition, continuum dilepton production may allow testing equivalent photon approximation formalism for description of strong electromagnetic fields emitted by ultrarelativistic heavy ions. The ALICE experiment has switched to continuous readout mode in Run 3, which improved reconstruction efficiency of vector mesons and enabled measuring dimuon continuum in the previously unavailable low-mass region. In this talk, preliminary results of analysis of coherent vector meson production and continuum dimuon production with the ALICE muon spectrometer will be discussed and compared with theoretical predictions.

M.Yu. Malyshev

  (HEPD, PNPI)

The Light Front Approach to QCD.
  Video
  Abstract:
In the framework of the light front approach to QCD, effective models for describing the mass spectrum of mesons and baryons, as well as their electromagnetic form factors, are considered.

A.Ye. Shevel

  (HEPD, PNPI)

Computing infrastructure in high energy physics experiments
(survey of the spring HEPIX-2024 April 15-19 2024).
  (Presentation)
  Video
  Abstract:
The reported intends to review the scientific program of the workshop with emphasize following topics: trends in laboratory computing resources, Linus distributives status and future, renovations in laboratory computing infrastructure, nearest future in computing components, relation to our local circumstances.

A.M. Zaitsev

  (IHEP, Serpukhov)

Experiments at U-70 Accelerator Complex (Serpukhov).
  Video
  Abstract:
The U-70 accelerator complex is used for experiments on a wide range of high-energy physics problems:
- kaon decays;
- hadron spectroscopy;
- relativistic nuclear physics;
- spin physics.
   The objectives of the research, characteristics of the beams and basic installations, the main experimental results and research plans for the near future are presented.

A.P. Serebrov

  (NRC KI - PNPI)

Analysis of experimental data on neutron decay for the possibility of the existence of a right-handed gauge vector boson.
  Video
  Abstract:
  (Abstract)

M.V. Tokarev

  (JINR, Dubna)

Z-scaling: status and perspectives.
  Video
  Abstract:
The present state of the z-scaling of hadron production in high energy proton and nucleus collisions is briefly reviewed. The basic concepts of the approach such as self-similarity, locality and fractality reflecting general features of particle interactions are discussed. Some results of analysis of hadron production in pp and AA collisions obtained in the framework of z-scaling are presented. The properties of data z-presentation for systematic analysis of inclusive cross sections over a wide range of collision energies, multiplicity densities, transverse momenta, and angles of various particles are discussed. A microscopic scenario of hadron production in terms of momentum fractions of colliding objects and scattered constituent is proposed. Physical interpretation of the model parameters – structural and fragmentation fractal dimensions and “specific heat”, is given. Universality of the form of the scaling function is discussed. Fractal entropy taking into account the structure of colliding and produced objects is considered. The notion of fractal cumulativity is introduced and a new conservation law for this quantity is formulated. Non-trivial dependence of the fractal entropy on the collision energy with decreasing transverse momentum was found. The corresponding irregularity of the specific heat is associated with possible indication of phase transition in nuclear matter. Experimental verification and development of the z-scaling are discussed.

O.V. Teryaev

  (JINR, Dubna)

Polarization in Reactions with Hadrons and Heavy Ions: Similarity and Distinction.
  Video
  Abstract:
The mechanism of baryon and vector meson polarization in pp, dd and AA collisions are compared. The sources of T-odd spin effects in T-invariant theories (like QCD) and possible interplay between them are discussed. The anomalous and thermodynamical polarization mechanisms in heavy-ion collisions lead to the effects of the same order but may be distinguished provided the data for various hyperons are available. The tensor polarization, contrary to the vector one, does not require the P-odd sources and may be related to entanglement of quarks and antiquarks.

A. Dzyuba

  (NRC KI - PNPI)

Hidden charm pentaquarks.
  (Presentation)
  Video
  Abstract:
The contribution will provide an overview of the experimental evidence on hidden charm pentaquarks. Such states were discovered by the LHCb experiment in the decays of beauty particles. In addition to LHCb measurements, experimental studies performed by the Belle and GlueX collaborations will be discussed.

G.А. Feofilov

  (SPbGU, Sankt-Petersburg)

Recent Highlights on Hadron Collisions with ALICE at the LHC.
  (Presentation)
  Video
  Abstract:
The overview includes several recent experimental observations by the ALICE collaboration in studies of a strongly interacting matter formed in ultrarelativistic Pb-Pb collisions at the LHC, as well as intriguing similarities in small systems like p-Pb and pp. Results on the medium effects on strange and charm particle yields, the shape of jets, the production of light (anti)(hyper)nuclei, and the residual strong interaction between strange, charm, and light hadrons are presented. The challenges encountered for Run 3 and the new perspectives of beauty and multi-charm studies in future Runs 4 and 5 are also discussed.

D.V. Karlovets

  (ITMO University)

Twisted particles: generation and potential applications in quantum physics.
  (Presentation)
  Video
  Abstract:
A review will be given of a relatively new but rapidly developing field at the intersection of quantum and neutron optics, electron microscopy and high-energy physics -- physics of massive "twisted" particles with orbital momentum: electrons, protons, neutrons, etc. Thanks to other selection rules when interacting with particles, fields and matter, in a number of problems particles in such quantum states can be used instead of spin-polarized particles; in other problems - especially for cold neutrons - they allow new experiments in QED and nuclear physics and obtain information not available with conventional plane-wave beams. I will also discuss the possibilities of generating such particles at high energy accelerators, incl. at JINR, and prospects for their use for high energy physics.

N.P. Tkachenko

  (IHEP, Serpukhov)

ATLAS and TOTEM: comments on assumed differential cross section oscillations at 13 TeV.
  (Presentation)
  Video
  Abstract:
Questions about the possible existence of oscillations at an energy of 13 TeV are considered in detail on the basis of a general model for describing differential cross sections in wide regions of energy changes and momentum transfer, published earlier in the PDG. It is shown that, given the available experimental data, raising the question of searching for such a subtle effect is premature.

Gao Jie

  (IHEP, China)

CEPC-SppC general status and perspectives.
  (Presentation)
  Video
  Abstract:
In this talk we will give the general trend of high energy physics development worldwide, and detailed CEPC-SppC development status. Future perspective about the CEPC construction and timeline will be presented.

A.V. Nefediev

  (P.N. Lebedev Physical Institute of the Russian Academy of Sciences)

Nature and properties of the doubly charmed exotic state Tcc+ in experiment and on a lattice.

Yu.G. Kudenko

  (INR of RAS, Moskow)

Neutrino Physics: Modern Status, Anomalies, Perspectives.
  Video
  Abstract:
Review of modern status of neutrino physics is presented in the talk.

А. L. Getalov

  (HEPD, PNPI)

Bacterial nano-ferrihydrite.
  (Presentation)
  Video
  Abstract:
Magnetic nanomaterials find the widest application. Current methods for chemical synthesis of nanoparticles are energy-intensive and use toxic chemicals, limiting biomedical applications. A promising new direction in this field is the use of biological objects for the production of inorganic nanoscale particles. Ferrihydrite nanoparticles (Fe2O3 * nH2O), synthesized by Klebsiella oxytoca bacteria during biomineralization of iron salt solutions from the culture medium, exhibit unique magnetic properties: they are characterized by antiferromagnetic order inherent in bulk ferrihydrite and spontaneous magnetic moment due to spin decompensation in nanoparticle sublattices. In the reviewed article, the authors from Krasnoyarsk investigated magnetic interparticle interactions and superparamagnetic blocking of powder systems of biogenic ferrihydrite nanoparticles using magnetometry and Mössbauer spectrometry. Two powder systems of nanoparticles were studied - biogenic ferrihydrite (average size 2.7 nm) and ferrihydrite, which underwent low-temperature annealing, as a result of which the average particle size (3.8 nm) increased and the organic shell burned out.

D.G. Levkov

  (INR RAS & ITMP MSU)

Light bosonic Dark Matter and axion stars.
  Video
  Abstract:
In the overview part of the talk I will discuss light bosonic (axion-like) Dark Matter. I will mention the models that predict the existence of light (pseudo)scalars, I will explain how such particles could have been produced in the early Universe and formed Dark Matter, and how they are searched experimentally. After this I will go into more detail about compact objects consisting of light Dark Matter - miniclusters and axion stars.

I. А. Alexandrov

  (SPbU)

Schwinger's mechanism and vacuum photon emission.
  (Presentation)
  Video
  Abstract:
In this talk, we will address the present status of theoretical and experimental investigations concerning the Schwinger mechanism of spontaneous electron-positron pair production from vacuum in strong electromagnetic backgrounds. This phenomenon is closely related to the vacuum emission of soft photons and also high-harmonic generation. We will discuss these effects and draw an explicit analogy between strong-field QED and atomic physics.

D.A.Ivanishchev

  (HEPD, PNPI)

Trigger system of the MPD experiment at NICA collider.
  (Presentation)
  Video
  Abstract:
The features of the trigger system of the MPD experiment at NICA collider are discussed in comparison with other experiments studying collisions of heavy relativistic nuclei. The results of a systematic study of capabilities of the trigger system of the MPD experiment in the collider mode to select events in collisions of light, intermediate masses and heavy nuclei at the energies of the NICA collider are presented.

M.G. Ryskin

  (PNPI)

Oscillations in elastic high energy amplitude.
  (Presentation)
  Video
  Abstract:
A weak (~ 1%) oscillations observed by TOTEM in elastic pp-scattering at 13 TeV correspond to the impact parameter b ~ 6-8 fm ! Theoretically the oscillations due to interference between the multi Pomeron exchange diagrams (analogous to the diffraction on black disk) were predicted in early 1970th however now the oscillations take place at |t| smaller than the first diffractive dip. IF this oscillations will be confirmed by ATLAS (?) this will be the qualitatively new phenomena.

S.V. Evdokimov

  (IHEP, Serpukhov)

Investigation of Neutral States Created in Meson-Nucleus Interactions in Hyperon-M Experiment.
  Video

A.A. Dzyuba

  (HEPD, PNPI)

Precision measurement of CP violation parameters in decays of B mesons at LHCb.
  (Presentation)
  Video
  Abstract:
IIn the Standard Model of particle physics, CP invariance is violated in the quark sector. This effect is associated with a non-zero complex phase of the elements of the unitary quark mixing matrix. It is expected that manifestations of New Physics beyond the Standard Model are related to noticeable violations of CP symmetry. Therefore, one of the strategies for searching for such effects is based on precision measurements of mixing matrix elements (or their ratios) and testing of its unitarity. The LHCb experiment performs these studies by examining the characteristics of beauty mesons decays. The results of precision measurements of CP violation parameters φs and sin(2β) [1,2] will be discussed.
          References:
   1. Phys. Rev. Lett. 132 (2024) 021801
   2. Phys. Rev. Lett. 132 (2024) 051802

Igor Strakovsky

  (GWU)

Search for Θ⁺ in К⁰p→K⁺n Reaction with JLab KLF.
  (Presentation)
  Video

I.A. Mitropolsky

  (ONI, PNPI)

Compact neutron sources: DARIA vs NG.
  (Presentation)
  Video
  Abstract:
In addition to S.V.Grigoriev's report, a brief review of compact neutron sources is provided. Attention is focused on the characteristics of neutron generators and their applications.

A.P. Serebrov

  (PNPI NRC KI)

Sterile neutrinos, dark matter, Standard Model with right-handed neutrinos, neutrino mass hierarchy and CP violation.
  (Presentation)
  Video

A.E. Ezhilov

  (HEPD, PNPI)

Precision measurement of Z boson transverse-momentum spectrum in proton-proton collision with 13 TeV in ATLAS experiment.
  Abstract:
This talk describes precision measurements of the transverse-momentum distribution of lepton pairs using the 2015-2016 data of the pp collisions at 13 TeV collected with the ATLAS detector at LHC. The comparison with the different theoretical predictions are also presented.

Logashenko Ivan

  (on behalf of CMD-3 collaboration) BINP (Novosibirsk)

Measurement of e⁺e^-→π⁺π^- cross section by CMD-3 and its implications to hadronic contribution to muon (g-2).
  (Presentation)
  Video

S.V. Grigoriev

  (PNPI NRC KI)

DARIA compact neutron source project for research by neutron scattering methods
  (Presentation)
  Video
  Abstract:
The world's leading neutron research centers are currently developing new generation neutron sources for research in the field of condensed matter physics. Compact neutron sources are designed to replace obsolete low- and medium-power reactors and open up opportunities for creating neutron scattering laboratories in scientific organizations and universities. Such a source initially yields neutron flux several orders of magnitude lower as compared to a large accelerator-type source; however, a significant part of these losses can be compensated by increasing the capture aperture and deep optimization of the instrument, including adapting the parameters of the accelerator, target and moderator to the needs of each specific installation using the source individually. We present a Russian initiative to create such a source - the DARIA project (compact neutron source Dedicated to Academic Research and Industrial Applications). The goal of the project is to develop and create first a prototype and then a network of compact neutron sources for the needs of neutron scattering.

N.P.Tkachenko

  (IHEP, Serpukhov)

АTLAS & TOTEM: √s = 13 TeV. Results or half-finished products?
  (Presentation)
  Video
  Abstract:
Detailed discussions of extracеed basic «forward» parameters ρ=ReT_N (s,t=0)/ImT_N (s,t=0), σ_tot= Im T_N (s,t=0), B={∂/∂t [dσ/dt]/[dσ/dt]}_(t=0) from the data, obtained by ТОТЕМ and ATLAS collaborations at √s=13 ТeV, in the Coulomb-nuclear interference region are presented.

M.M. Kirsanov

  (INR RAS)

Recent results and plans of the NA64 experiment at the CERN SPS.
  Video
  Abstract:
Thermal dark matter models with particle masses below the electroweak scale can provide an explanation for the observed relic dark matter density. This would imply the existence of a new feeble interaction between the dark and ordinary matter. The main purpose of the NA64 experiment is a search for sub-GeV dark matter production using the method of missing energy signature. The searches are performed at the H4 beam line at the CERN SPS. This line is mainly designed to provide 100 GeV electron beam. The analyzed statistics corresponds to $9.37\times10^{11}$ electrons on target (EOT) collected during 2016-2022 runs. The analysis of this statistics allowed us to probe for the first time the well motivated region of parameter space of benchmark thermal scalar and fermionic dark matter models. Additional statistics of about $6\times10^{11}$ was collected in the 2023 run. In addition to the main 100 GeV electron-beam measurement, NA64 is also developing a positron-beam program with several runs at different energies, to explore the ~ 100 MeV mediator mass range by exploiting LDM production via resonant $e^+e^-$ annihilation. This search is also supported by a dedicated ERC project, the "POsitron resonant annihilation intO dark mattER" (POKER) project, lead by INFN-Genova. An early test run already demonstrated the feasibility of the new technique, allowing to set competitive new limits in a limited mass region despite the much lower accumulated statistics.
    The variant of the NA64 detector for the searches of DM in the muon beam, called NA64mu, is also developed. It uses part of subdetectors of NA64e and a number of additional subdetectors. The purpose is to search for DM coupled only to second and third generations of leptons, suggested to explain the (g-2) anomaly and to improve sensitivity in the region of mediator masses above ~300 MeV. NA64 performed and plans also a number of other searches, such as the search for ALP coupled to gammas, search for X boson decaying to electrons, search of DM in the hadron beams, search for mu - tau conversion.

A.I. L'vov

  (P.N. Lebedev Physical Institute of RAN, Moscow)

Compton Effect and Nucleon Polarizability.
  Video

S.I. Vorobyov

  (HEPD, PNPI NRC KI, Gatchina)

μSR-investigations of materials with various types of putting in magnetic order at muon channel of synchrocyclotron SC-1000.
  (Presentation)

D.S. Gorbunov

  (INR RAS)

Models with light particles of Dark Matter.
  Video
  Abstract:
Traditionally, models of Dark Matter are divided according to the mechanism of particle creation into thermal and non-thermal. An example of the first is WIMPs. The second class is much richer. Using the simplest example of a scalar massive particle, we will discuss several mechanisms for the creation of Dark Matter particles. Then we'll look at some realistic models whose predictions are being tested in modern particle physics experiments.