April 2 of 2024 year, 10:30 |
I. А. Alexandrov
(SPbU) |
Schwinger's mechanism and vacuum photon emission.
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.
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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.
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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.
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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.
|