Barzakh Anatoly Efimovoch

  (HEPD PNPI)

Isotonic relationships of charge radii and boundaries of the region of octupole deformation of nuclei at Z> 82.
  (Presentation)
  Video

E.A. Kriukova

  (INR RAS & ITMP MSU)

Hypothetical vector particles with masses of the order of light hadron masses in fixed‑target experiments with hadron beams (based on a PhD thesis).
  (Presentation)
  Video
  Abstract:
   The report will address the production of hypothetical vector particles, dark photons, with masses in the range of 0.4–1.8 GeV, in collisions of proton and pion beams with a fixed target.
   The first chapter of the thesis is devoted to the study of elastic proton bremsstrahlung accompanied by dark photon production. The cross section of this process will be derived analytically, taking into account a non‑zero momentum transfer between protons. It will be shown that the obtained result is in good agreement with the Weizsäcker–Williams approximation.
   The second chapter examines the contribution of the Pauli electromagnetic form factor to inelastic proton bremsstrahlung. A factorization of the inelastic proton bremsstrahlung cross section will be performed, and new splitting functions associated with the contribution of the Pauli electromagnetic form factor will be derived. Additionally, updated sensitivity curves for the T2K, DUNE, and SHiP experiments will be obtained in the context of dark photon searches.
   The third chapter of the thesis investigates inelastic charged pion bremsstrahlung. For the typical energies of real pion beam experiments, the inapplicability of the leading order of chiral perturbation theory — previously used to estimate the inelastic pion bremsstrahlung cross section — will be demonstrated. Instead, for the production of dark photons with masses in the range of 0.4–1.2 GeV, a new method for estimating the inelastic pion bremsstrahlung cross section in the quasi‑real approximation, using the Dawson correction, will be proposed. Furthermore, for dark photons with masses in the range of 1.2–3.5 GeV, the contribution of a competing analogue of the Drell–Yan process will be estimated.

Burmasov N.A.

  (HEPD PNPI)

Upcgen Event Generator: Modeling Two-Photon and Photonuclear Processes in Ultraperiferous Heavy Ion Collisions.
  (Presentation)
  Video

Davydov Yuri Ivanovich

  (JINR, Dubna)

Development of precision wire detectors and installation for muon decay study.
  (Presentation)
  Video
  Abstract:
   TWIST experiment (TRIUMPH, Vancouver, Canada), aimed to measure with record accuracy of Michel ρ, δ and Pµ parameters ξ in positive decays muons. To achieve this goal, it was necessary to create a spectrometer with a high geometric accuracy and measure the energy of decay positrons with relative accuracy at a level better than 10-3.
   The report examines the methodology for creating wire detectors and features of the TWIST spectrometer. Data analysis and evaluation methods discussed systematic errors in determining Michel parameters. Obtained parameters Michel's accuracy was about an order of magnitude superior to pre-existing results and entered Particle Data Group data.

Dr. Bing Liu (Head of the p-B Fusion Reaction Group) and Dr. Zhi Li, Research Engineer, p-B Fusion Reaction Group

  (ENN Science & Technology Development Co., Ltd, China)

Significance and challenges of nuclear spin polarization in proton‑boron fusion.
  (Presentation)
  Video
  Abstract:
ENN Energy Research Institute, an affiliate of ENN Group, has been dedicated to research on spherical torus (ST) proton-boron (p-¹¹B) fusion energy since 2017. Using two generations of spherical torus fusion experimental devices (EXL-50, EXL-50U), ENN has enabled rapid iteration in both theoretical and engineering fields. This presentation will highlight recent progress, introduce the concept of achieving ignition in p-¹¹B fusion with the assistance of nuclear spin polarization, and analyze the key challenges and difficulties associated with this approach. In addition, a collaborative experiment will be proposed to carry out the first measurement of the polarized p-¹¹B reaction in the low-energy region.

A.P. Serebrov

  (NRC Kurchatov institute - PNPI)

Baryonic and Leptonic Asymmetries of the Universe.
  (Presentation)
  Video

O.Yu. Andreev

  (SPBSU & NRC KI - PNPI)

Bound–bound muon transitions in muonic atoms with electron–positron pair production.
  (Presentation)
  Video
  Abstract:
Bound–bound muon transitions in muonic atoms, accompanied by the production of electron–positron pairs, were studied. It was shown that for ions with a nuclear charge of Z ≥ 24, transitions of bound muons from low-lying excited states to the 1s ground state can lead to the production of electron–positron pairs. It was found that the probability of such transitions for states with nonzero orbital angular momentum is determined primarily by the Breit interaction. It was also shown that, in general, pair production occurs predominantly through the decay of 2p states. Thus, the Breit interaction plays a key role in the process of electron–positron pair production in bound–bound muon transitions. This process opens a unique opportunity to study quantum electrodynamics in strong fields and also represents a little-studied class of non-radiative transitions accompanied by the production of electron-positron pairs.

A.P. Serebrov

  (NRC Kurchatov institute - PNPI)

Precision studies of neutron decay and the need to expand the Standard Model.
  (Presentation)
  Video

A.A. Dzyuba

  (HEPD PNPI, NRC KI)

LHCb results on measuring CP-impairment effects.
  (Presentation)
  Video