September 17 of 2024 year, 10:30 |
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).
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.
|
September 17 of 2024 year, 10:30 |
Burmasov N.A.
(HEPD, PNPI) |
Coherent vector meson photoproduction and dimuon
continuum production with the ALICE experiment at the LHC.
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.
|
July 2 of 2024 year, 10:30 |
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.
|
June 25 of 2024 year, 10:30 |
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.
|
June 20, 2024 year, 14:30 Joint Seminar HEPD - TPD |
I.V. Voronchikhin
(Tomsk Polytechnic University) |
Attention! Postponement of the seminar! (Tentatively for September)
Productuon of dark matter mediators at fixed target experiments.
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).
|
June 18 of 2024 year, 10:30 |
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.
|
June 13, 2024 year, 14:30 Joint Seminar HEPD - TPD |
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)
|
June 11 of 2024 year, 10:30 |
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.
|
June 04 of 2024 year, 14:30 |
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.
|
May 30, 2024 year, 14:30 Joint Seminar HEPD - TPD |
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.
|
May 28 of 2024 year, 10:30 |
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.
|
May 23, 2024 year, 11:00 Joint Seminar HEPD - TPD |
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.
|
May 21 of 2024 year, 14:30 |
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.
|
May 14 of 2024 year, 10:30 |
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.
|
April 25, 2024 year, 11:00 Joint Seminar HEPD - TPD |
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.
|
April 23 of 2024 year, 10:30 |
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.
|
April 16 of 2024 year, 10:30 |
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.
|
April 11, 2024 year, 14:30 Joint Seminar HEPD - TPD |
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.
|
April 2 of 2024 year, 10:30 |
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.
|
March 26 of 2024 year, 10:30 |
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.
|
March 14, 2024 year, 14:30 Joint Seminar HEPD - TPD |
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.
|
March 12 of 2024 year, 10:30 |
S.V. Evdokimov
(IHEP, Serpukhov) |
Investigation of Neutral States Created in Meson-Nucleus Interactions in Hyperon-M Experiment.
Video
|
March 05 of 2024 year, 10:30 |
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
|
February 29, 2024 year, 14:30 Joint Seminar HEPD - TPD |
Igor Strakovsky
(GWU) |
Search for Θ⁺ in К⁰p→K⁺n Reaction with JLab KLF.
(Presentation)
Video
|
February 27 of 2024 year, 10:30 |
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.
|
February 22, 2024 year, 11:00 Joint Seminar HEPD - TPD |
A.P. Serebrov
(PNPI NRC KI) |
Sterile neutrinos, dark matter, Standard Model with right-handed neutrinos, neutrino mass hierarchy and CP violation.
(Presentation)
Video
|
February 20 of 2024 year, 10:30 |
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.
|
February 15, 2024 year, 14:30 Joint Seminar HEPD - TPD |
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
|
February 13 of 2024 year, 10:30 |
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.
|
February 06 of 2024 year, 10:30 |
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.
|
February 1, 2024, 14:30 Joint Seminar HEPD - TPD |
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.
|
January 30 of 2024 year, 10:30 |
A.I. L'vov
(P.N. Lebedev Physical Institute of RAN, Moscow) |
Compton Effect and Nucleon Polarizability.
Video
|
January 23 of 2024 year, 10:30 |
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)
|
January 18, 2024, 11:00 Joint Seminar HEPD - TPD |
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.
|