December 19, 2023, 10:30 |
O.V. Miklukho
(HEPD, PNPI NRC KI, Gatchina) |
Observation of the structure in the spectrum of scattered protons
at an angle of 21o degree in the momentum region,
covering the quasi-elastic pN peak, in the inclusive reaction (p, p’)
with the 12C nucleus at an energy of 1 GeV.
(Presentation)
Abstract:
The observed structure in the momentum distribution of secondary protons may be partially due to diffraction
scattering of beam protons on constituents of the carbon nucleus.
|
December 14, 2023, 14:30 Joint Seminar HEPD - TPD |
M.G. Ryskin
(PNPI NRC KI, Gatchina) |
Large Rapidity Gaps in proton-nucleus interaction.
(Presentation)
Video
Abstract:
The events with Large Rapidity Gap (LRG) are attractive for the New/BSM Physics searching since in such events
there is no background caused by the underlying/MPI interactions. Therefore, it is important to understand the structure
and the cross sections of the LRG events. We present the corresponding model and analyse the cross-section of events with
Large Rapidity Gaps observed in the proton-proton (7 TeV) and the proton-lead (8.16 TeV) collisions by the CMS
collaboration. The role of the transverse size of elementary pN amplitude (which is larger than the diffusion edge
width of the lead ion) is discussed. We emphasize that the cross-section of incoming proton dissociation caused
by the photon radiated off the lead ion is close to the value of dσ/d∆η^F measured by the CMS, and it is not clear why
there is no room in the data for the Pomeron-induced contribution.
|
December 12, 2023, 10:30 |
D. Pudzha
(HEPD, PNPI NRC KI, Gatchina) |
Experiment AMS-02 at International Cosmic Station.
Video
Abstract:
The Alpha Magnetic Spectrometer (AMS), a particle physics experiment,
operates aboard the International Space Station. This presentation
delves into the purpose and design of AMS, emphasizing its
unique position in space, which allows for the detection
of cosmic rays unimpeded by Earth's atmosphere. We explore
its major scientific objectives, including the search for antimatter,
the study of cosmic ray composition, and the quest to understand
dark matter. The presentation highlights key discoveries
made by AMS and the implications of these findings
in particle physics and cosmology. By analyzing the data collected by AMS,
we discuss how these findings challenge existing theories and
open new avenues in understanding the universe's fundamental properties.
|
December 7, 2023, 14:30 Joint Seminar HEPD - TPD |
B. Wojtsekhowski
|
Search for a dark photon with positron beam in the JLab.
Video
Abstract:
We will present a plan of experimental search for a dark photon by means of a low energy electron-positron
collider made using a GeV positron beam on the atomic electrons in a hydrogen target. Projected detectable
coupling of a dark photon and an electron ε2 is 108 times lower than for a QED photon.
|
December 5, 2023, 10:30 |
L.V. Grigorenko
(JINR, Dubna) |
Research design and scientific program of perspective Compton source of monochromatic gamma quanta in NCPM.
(Presentation)
Video
|
November 30, 2023, 14:30 Joint Seminar HEPD - TPD |
A.V. Nefediev
(LPI RAS) |
On the exotic hadrons consisting of heavy quarks.
(Presentation)
Video
|
November 28, 2023, 14:30 Joint Seminar HEPD - TPD |
A.M. Fedotov
(NRNU "MEPhI") |
QED processes in the extreme intensity laser fields.
Video
|
November 23, 2023, 14:30 Joint Seminar HEPD - TPD |
E.L. Kryshen
(HEPD, PNPI NRC KI) |
Photoproduction of vector mesons in ultraperipheral collisions at the LHC.
(Presentation)
Video
Abstract:
Ultraperipheral collisions (UPC) of nuclei at the Large Hadron Collider allow one to explore photonuclear interactions
at high energies. In this talk, results of the vector meson photoproduction studies in UPCs in the ALICE experiment
are presented and compared with theoretical calculations obtained within the Gribov-Glauber model and in the perturbative QCD.
In addition, prospects for future UPC measurements at the LHC are also discussed.
|
November 16, 2023, 14:30 Joint Seminar HEPD - TPD |
V.A. Khoze
|
ONLY O N L I N E !
CENTRAL EXCLUSIVE PRODUCTION @ LHC ( Part 2) – Di-meson saga.
Video
|
November 14, 2023, 10:30 |
A.E.Shevel
(HEPD, PNPI NRC KI) |
Monitoring of large technical installations.
(Presentation)
Video
Abstract:
A quick look at the features of large technical installations (large physics detectors or similar)
and their characteristics is done. General monitoring tasks of such installations are discussed.
The reporter plans to present quick review of interesting/useful features/characteristics
of the monitoring systems. Observation of the state of monitoring-system development and
administrator’s role at running monitoring systems is planned to be presented as well.
Also, it is supposed the direction of improvements in monitoring systems with
Artificial Intelligence (AI) technology at the nearest future.
Dear colleagues, here is a simple example of using the site perplexity.ai (see attachment). Registration on the site is free.
(example from perplexity.ai)
|
November 7, 2023, 10:30 |
V.V. Lukashevich
(HEPD, PNPI NRC KI) |
Symmetry Violations in Neutron Scattering and Lorentz Group.
(Presentation)
Abstract:
Symmetries in neutron scattering for spin-dependent interactions are discussed.
It is shown that the transformations of spinors in these cases are related to the Lorentz group.
|
November 2, 2023, 14:30 Joint Seminar HEPD - TPD |
M.G. Ryskin
(ThD, PNPI NRC KI) |
Color reconnection and inclusive J/ψ hadroproduction.
(Presentation)
Video
Abstract:
At high energies, one of the most important stages in the description of hard inelastic hadron-hadron interactions
is hadronization - the transition from a large number of colored partons, produced in multiparton QCD interactions,
to the colorless hadrons registered in the detector. At this stage, the structure of color flows can be changed so as
to reduce the total length of color strings, combining partons into colorless clusters of the smallest possible mass.
This is called color reconnection. As a result, the distributions of secondary hadrons change, which, in particular,
makes it possible to better describe: the growth of the average transverse momentum with increasing multiplicity;
the production of new baryons; inclusive cross sections for the production of J/ψ mesons.
|
October 31, 2023, 10:30 |
O.V.Zenin
(Protvino, NRC KI PNPI) |
Hadronic contribution to the anomalous magnetic moment of the muon: assessment using the IHEP total cross-section database.
(Presentation)
Video
|
October 24, 2023, 10:30 |
V.V. Chulikov
(HEPD, NRC KI PNPI) |
Studying the production of charmed baryons in the LHCb experiment.
Abstract:
The work status in the LHCb experiment on the study of the production of charm baryons is presented.
Updates on the results of the work by the LBP HEP-division on the production of $\Xi_c^+(2815)$
and $\Xi_c^0(2645)$ baryons in pp collisions at the LHC are discussed.
|
October 19, 2023, 14:30 Joint Seminar HEPD - TPD |
V.A. Khoze
|
CENTRAL EXCLUSIVE PRODUCTION @ LHC (selected topics).
Video
Abstract:
We discuss the special features of the Central Exclusive Production (CEP) at hadron colliders with an emphasis on the LHC.
The centrally produced system in these processes is separated from the outgoing protons (or products of their dissociation)
by large rapidity gaps (LRGs). The gaps could be induced by the Pomeron, Odderon, or photon (W,Z-bosons exchanges.
We focus on the Pomeron-mediated reactions and provide a selected shopping list of what to measure in general and what for
at the LHC, both with tagged forward protons (ATLAS and CMS) and in the Rapidity Gap environment (LHCb, ALICE).
Of particular interest are the novel QCD tests, searches for new heavy objects, such as new resonances, glueballs,
Instantons, and signals for BSM physics. Selection rule feature of the CEP provides a unique opportunity
to analyze spin-parity of the central system and to probe the CP-structure of the new states. Due to Sudakov suppression
of the QCD-induced processes at large masses of the central system the photon-photon fusion mechanism dominates allowing
one to consider the LHC as a photon-photon collider.
|
October 17, 2023, 10:30 |
Yu.G.Naryshkin
(NRC KI PNPI) |
The first observation of the “quantum entanglement” effect in the analysis of spin correlations in the pair production of top and anti-top quarks in the ATLAS experiment.
(Presentation)
Video
Abstract:
"Quantum entanglement” is one of the most extraordinary properties of quantum mechanics.
If particles are entangled, the state of one particle cannot be described independently
from the other. Up to now the study of "quantum entanglement" were performed
at non-relativistic energies, typically utilizing photons or electrons.
In the ATLAS experiment by the study of spin correlations in the pair production
of top and anti-top quarks in proton-proton collisions at the energy of √s=13 TeV,
the effect of “quantum entanglement” was observed for the first time
at the highest energy. This is also the first-ever observation of the
"quantum entanglement" between a pair of quarks.
|
October 12, 2023, 14:30 Joint Seminar HEPD - TPD |
I.I. Strakovsky
(GWU) |
Is the LHCb Pc (4312)+ Plausible in the GlueX γ p →J/ψ p Total Cross Sections ?
(Presentation)
Video
Abstract:
New high-statistics total cross-section data for γ p→ J/ψ p from the gluonic excitation (GlueX) experiment are fitted in a search
for the exotic Pc (4312)+ state observed by the Large Hadron Collider beauty (LHCb) Collaboration.
The integrated luminosity of this GlueX experiment was about 320 pb−1. The fits show that destructive interference involving
an S-wave resonance and associated non-resonance background produces a sharp dip structure about 77 MeV below the LHCb mass,
in the same location as a similar structure is seen in the data. Limitations of the employed model and the need for improved statistics are discussed.
|
October 10, 2023, 10:30 |
V.P. Neznamov
(VNIIEF, Sarov) |
Quantum electrodynamics with empty fermion vacuum. Possibilities of experimental verification.
(Presentation)
Video
|
October 5, 2023, 14:30 Joint Seminar HEPD - TPD |
F.F. Karpeshin
(D.I.Mendeleyev Institute for Metrology VNIIM) |
The resonant optical pumping of the 8.3-eV isomer 229mTh.
(Presentation)
Video
Abstract:
The most probable candidate for the role of a nuclear optical standard is the 8.2-eV isomer of the 229mTh isotope of the thorium nucleus.
Ways of using the resonant properties of the electron shell as an optical resonator to create laser nuclear technologies necessary
for the optical pumping of nuclear isomers and other manipulations of atomic nuclei leading to the creation of a next-generation
frequency standard and nuclear-optical clocks based on them are discussed. Deep relations between the physics of resonance electron-nuclear
interactions and the true solution of the thorium puzzle are shown.
|
October 3, 2023, 10:30 |
V.V.Sulimov
(NRC KI PNPI) |
ONLY O N L I N E ! Gravitational waves. Searches and discoveries.
(Presentation)
|
September 26, 2023, 10:30 |
V.T. Kim
(NRC KI PNPI) |
High-energy scattering processes within next-to-leading-logarithmic (NLL) BFKL evolution.
Video
Abstract:
Problems of the next-to-leading-logarithmic Balitsky-Fadin-Kuraev-Lipatov (NLL BFKL) evolution application
for high-energy scattering processes are discussed.
|
September 19, 2023, 10:30 |
Nechiporenko Yu. V.
(NRC KI PNPI, SPbPU) |
Superheavy nuclides and prospects for their study.
Video
Abstract:
Superheavy nuclides are exotic objects of nuclear world,
and the report reveals interest in their study.
The existence of superheavy island of stability is discussed.
The possibility of synthesizing such nuclides in the laboratory
and their existence in nature is being explored. Experiments
on precise mass measurements of superheavy nuclides are considered.New hints of manifestation of BFKL evolution at 2.76 and 7 TeV collision energies are obtained.
|
September 12, 2023, 10:30 |
A.Yu. Egorov
(NRC KI PNPI, SPbPU) |
Search for the BFKL effects in dijet production with large rapidity separation in pp collisions at LHC energies
(Presentation)
Video
Abstract:
The measurements by the CMS experiment of the set of observables, which are sensitive to possible signals of BFKL evolution, are presented/
The obtained results are compared with Monte Carlo generator predictions and analytical calculations based on both DGLAP and BFKL evolution, respectively. New hints of manifestation of BFKL evolution at 2.76 and 7 TeV collision energies are obtained.
|
20 June, 2023, 10:30 |
D.V. Fedorov
(HEPD PNPI) |
CERN-MEDICIS: Production of Promising Radionuclides for Nuclear Medicine
(Presentation)
Video
Abstract:
CERN-MEDICIS is the only European facility which dedicates its full
program to the production and delivery of medical isotopes
for research in radiopharmaceutical science, operating in isotope mass
separation mode. The description of CERN-MEDICIS facility
and a pilot study of radiopharmaceutical, based on 169Er, produced at
CERN-MEDICIS are presented.
|
13 June, 2023, 10:30 |
P.L. Molkanov
(HEPD PNPI) |
Study of gold isotopes by laser spectroscopy.
(Presentation)
Video
|
June 8, 2023, 14:30 Joint Seminar HEPD - TPD |
V.F. Ezhov
(PNPI NRC KI, Gatchina) |
Neutron lifetime measurements: status and prospects.
(Presentation)
Video
Abstract:
Precision measurements of the neutron lifetime are one of the tests of the standard electroweak model.
In combination with measurements of other neutron beta decay correlation coefficients, the neutron lifetime makes it possible to
determine the Vud element in the Kabbibo-Kobayashi-Maskawa quark mixing matrix. The neutron lifetime is also one of the key
parameters for determining the yield of light elements during nucleosynthesis during the first few minutes of the Universe's existence.
Magnetic storage of ultracold neutrons (UCN), in contrast to storage in material traps, allows one to control the loss
of neutrons during the measurement of the lifetime of neutrons. It is possible to realize this advantage of the magnetic
storage of the UСN only with the help of a magnetic shutter. Without this unique opportunity, experiments with magnetic storage
are indistinguishable from experiments with storage in material traps. The problems and systematics in experiments on measuring
the lifetime of neutrons using magnetic storage of UСN are discussed.
|
6 June, 2023, 10:30 |
S.I.Manaenkov
(HEPD PNPI) |
Phenomenology of coherent electroproduction of vector mesons on a spinless target.
(Presentation)
Video
|
June 1, 2023, 14:30 Joint Seminar HEPD - TPD |
Yu. L. Dokshitzer
|
Gribov Light Quark Confinement Scenario.
(Presentation)
Video
|
May 30, 2023, 10:30 |
A.E.Barzakh
(HEPD PNPI) |
Magnetic moments of nuclei near magic numbers.
(Presentation)
Video
Abstract:
Magnetic moments of Tl isotopes/isomers in the vicinity of the magic number N=126 were measured
by in-source laser spectroscopy with LIST technique at ISOLDE. More reliable estimation of the proton
gL-factor renormalizaion was obtained. Do the "singular points" in the isotopic behaviour of the magnetic
moment point to the direction of the further
development of the mean field theories?
|
May 23, 2023, 10:30 |
N.I.Voropaev
(HEPD PNPI) |
Precision Measurement of Rare and Ultra-Rare Pion decays, Experiment PIONEER.
(Presentation)
Video
Abstract:
PIONEER is a new generation rare and ultra-rare pion decay experiment. The aim is a precision measurement
of pion decays with appearance of positron. The experiment is motivated by several data
pointing towards the violation of lepton flavor universality.
|
May 18, 2023, 14:30 Joint Seminar HEPD - TPD |
G.I. Rubtsov
(INR RAS) |
Problems and challenges of ultrahigh energy cosmic ray physics.
(Presentation)
Video
Abstract:
We present an overview of actual problems and recent scientific results in the physics of the ultrahigh energy cosmic rays (above 10^18 eV).
The author of the report is a member of the Telescope Array collaboration (TA), the largest cosmic ray observatory in the Northern Hemisphere.
TA and the Pierre Auger experiment in the Southern Hemisphere have collected unprecedented event statistics, which allows us to come close to solving the problem
of the origin of cosmic rays at the highest energies. The latest results on the anisotropy, chemical composition, and energy spectrum of cosmic rays,
as well as the results of a search for ultrahigh energy neutral particles (photons and neutrinos) are presented. The results on the anisotropy
of cosmic rays are considered in the context of the search for sources. A description of the state of research on the problem of muon excess
in extensive air showers is given. The interdisciplinary results of the Telescope Array experiment related to the physics of thunderstorms are discussed.
|
May 16, 2023, 10:30 |
A.B. Gridnev
(HEPD PNPI) |
Can the X17 boson be a hadron.
Abstract-2:
Data on pion-nucleon elastic scattering contradict the hypothesis that the X17 boson is a hadron.
|
May 16, 2023, 10:30 |
S.G. Barsov
(HEPD PNPI) |
Anomaly of internal pair conversion ( X17 ). New measurements in the Atomki and other planned experiments.
(Presentation)
Video
Abstract-1:
New evidences for the anomaly of internal pair conversion found in He-4 and C-12 by group from
Atomki (Debrecen, Hungary) to be in agreement with existence of a hypothetical X17 particle
(see also M.B.Ghalov, HEPD seminar, 20.06.2017) are presented. Taking into account that none
of experiment directly searching for a light boson production confirm X17 so far, a number of
experiments aimed to check the Atomki results are under preparation around the world.
|
April 25, 2023, 10:30 |
S.A. Eliseev
(M. Plank Institute, Heidelberg, Germany) |
Penning traps for fundamental physics by the example of SHIPTRAP and PENTATRAP.
Abstract:
High-precision Penning trap mass spectrometry is the most precise technique employed to measure
masses of nuclides with half-lives as short as a few ten ms. Currently, there are about a dozen high-
precision Penning-trap mass spectrometers located in North America and Europe. The majority of them
are part of various Rare Ion Beam (RIB) facilities and aim at measurements of masses of short-lived
nuclides with fractional uncertainties down to 10-9. The other group encompasses four ultra-precise
Penning trap mass spectrometers. Their major goal are mass-ratio measurements on long-lived and stable
nuclides with fractional uncertainties of as small as a few ppt.
In my talk I will make you acquainted with Penning-trap mass spectrometry by the example of two facilities
– SHIPTRAP and PENTATRAP. The focus of the talk will be laid on PENTATRAP. It aims to perform mass-
ratio measurements on a very broad range of long-lived nuclides to assist, e.g., experiments on the
determination of the neutrino mass, on the search for the fifth force, on the investigation of atomic
metastable states that can be suitable ion clock transitions and so on. I will present latest achievements
and future plans with PENTATRAP.
|
April 18, 2023, 10:30 |
V.A. Murzin
(NRC KI - PNPI) |
Searches for heavy resonances by CMS.
(Presentation)
Abstract:
An overview of the recent results on search for heavy resonances by the CMS collaboration at LHC.
|
April 13, 2023, 14:30 Joint Seminar HEPD - TPD |
A.V. Ivanchik, corr. member of the RAS
(Ioffe Institute) |
Neutrino astrophysics. Cosmological neutrinos.
Video
Abstract:
Being the most mysterious particle of the Standard Model, the neutrino has also opened up new possibilities in astrophysics. Thanks to neutrinos, a new view of the Universe is emerging. The high penetrating power of neutrinos make it possible to see the interiors of stars, to investigate the mechanisms of the emergence of ultrahigh-energy cosmic rays in the active nuclei of galaxies. When a star explodes, a neutrino flash informs us about this event several hours before electromagnetic radiation. The neutrino also plays one of the key roles in cosmology, being one of the known most abundant particles in the Universe. Neutrinos at the radiation-dominated stage together with photons determine the dynamics of the expansion of the Universe. Later, becoming nonrelativistic, the neutrino increases the fraction of nonrelativistic matter Ωm in the Universe, which previously consisted of contributions from cold dark matter and baryonic matter. The fact that neutrinos influence the evolution of the Universe requires to accounting for it when determining the cosmological parameters from the analysis of the anisotropy of the CMB. At present, there are no doubts about the existence of cosmological neutrinos, but, unfortunately, due to the smallness of their energies, it has not yet been possible to register them directly. However, there are already projects for such experiments, and if we manage to register cosmological neutrinos in the future, then we will directly see the first minutes and hours of the evolution of the Universe after its birth.
|
April 11, 2023, 10:30 |
M.D. Seliverstov
(NRC KI - PNPI) |
Investigation of processes of effusion, surface and laser
ionization in the proposed Target -
Ion Source Unit for the IRINA facility.
(Presentation)
Video
Abstract:
Processes of the effusion and ionization (laser and surface) in the Target - Ion Source
(for the IRINA facility project) were investigated using Monte Carlo method.
Estimations were made for the release time of atoms and ions, and laser ionization
efficiency (including possible recombination and re-ionization).
|
April 6, 2023, 14:30 Joint Seminar HEPD - TPD |
I.I. Strakovsky
(GWU) |
Threshold vector meson photoproduction: from omega to upsilon.
(Presentation)
Video
Abstract:
High-accuracy ϒ-meson photoproduction data from EIC and EicC experiments will allow the measurement of the near-threshold total cross section of the reaction γp → ϒp from which the absolute value of the ϒp-scattering length can be extracted using a vector-meson dominance model. For this evaluation, we used ϒ-meson photoproduction quasi data from the QCD approach (the production amplitude were factorized in terms of the gluonic generalized parton distributions and the quarkonium distribution amplitude). A comparative analysis of ϒp with the recently determined scattering lengths
for ωp, ϕp, and J/ψp using the A2, CLAS, and GlueX experimental data is performed. The role of the ''young'' vector meson effect is evaluated.
|
April 4, 2023, 10:30 |
V. A. Oreshkin
(NRC KI - PNPI) |
Measurements of the Higgs boson properties: current status at CMS, LHC.
(Presentation)
Abstract:
In the recent years, CMS continued to analyze the full Run-2 dataset. Taking advantage of the full recorded luminosity of 137 fb-1 and center-of-mass energy of 13 TeV, and novel analysis techniques, CMS enhanced precision of the previously measured properties of the Higgs boson and found evidences for certain Higgs couplings. The recent results include an improved precision of the Higgs boson mass. Also, differential measurements and CP structure of its Yukawa couplings, e. g. couplings to heavy fermions such as top quark and tau lepton, were studied. In the sector of second generation fermions, an evidence of the Higgs boson coupling to muons was obtained with a significance of 3σ, as well as an upper bound on the Higgs-charm coupling, for the first time. Besides the main 5 production and 5 decay modes, observed at statistical significances > 5σ, a more statistically limited and complicated decay of H → Z𝛾 was observed at statistical significance of 2.7σ. The measurement of the Higgs width, which will help to further constrain Higgs boson branching fractions to invisible or undetected decays, was done in an indirect way using its off-shell production, with the first evidence of the off-shell production observed at a significance of 3.6σ.
|
March 30, 2023, 14:30 Joint Seminar HEPD - TPD |
Vladimir M. Shabaev
(SPbSU & NRC KI - PNPI) |
How to observe the vacuum decay in low-energy collisions of heavy ions.
Video
Abstract:
It is known that in slow collisions of two bare nuclei with the total charge number larger than the critical value, Z_1+Z_2 > Z_c =173,
the initially neutral vacuum can spontaneously decay into the charged vacuum and two positrons. Detection of the spontaneous emission of positrons would
be the direct evidence of this fundamental phenomenon. However, the spontaneous positron emission is generally masked
by the dynamical positron emission, which is induced by a rapidly changing electric field created by the colliding nuclei.
For many years it was believed that the vacuum decay can be observed only in collisions with nuclear sticking,
when the nuclei are bound for some period of time due to nuclear forces.
But to date there is no evidence for the nuclear sticking in such heavy-ion collisions.
In our recent papers [I.A. Maltsev et al., PRL, 2019; R.V. Popov et al., PRD, 2020],
it was shown that the vacuum decay can be observed without any sticking of the nuclei.
This can be done via measurements of the pair-production probabilities or the positron spectra for a given set of nuclear trajectories.
The results of this study will be presented in the talk. In addition, some other interesting problems appearing in quantum electrodynamics at strong-coupling regime will be discussed.
|
March 28, 2023, 10:30 |
M. V. Smirnov
(Friedrich-Alexander University of Erlangen-Nuremberg, Erlangen Centre for Astroparticle Physics (ECAP), Erlangen, Germany)
|
Neutrino physics in the experiment KM3NeT/ORCA.
Video
Abstract:
The underwater neutrino telescope ORCA, part of the European Neutrino Observatory KM3NeT, is located in the Mediterranean Sea.
Due to the high density of digital optical modules, ORCA is sensitive to atmospheric neutrino oscillations.
Detector deployment continues. The main purpose of the experimental campaign is to determine the neutrino mass hierarchy.
|
March 23, 2023, 10:30(!) Joint Seminar HEPD - TPD |
Aurel Bulgac
(UW)
|
Unraveling The Many Facets of Non-Equilibrium Fission Dynamics: A Real-Time Quantum Approach.
Video
Abstract:
When comparing nuclear fission at the venerable age of almost 84 years old with other quantum many-body systems
(superconductivity, superfluidity, quantum Hall effect, fractional quantum Hall effect, magnetism, etc.)
it is surprising to find out how little is known and microscopically justified for this complex quantum non-equilibrium process.
In the last decade a significant advancenment was achieved in modeling and disentangling aspects of fission, by means of a pure quantum approach.
The level of agreement with observations, without the resort to any unverified theoretical assumptions,
uncontrolled numerical approximations, or phenomenology and incorporating only the basic input needed
to reproduce most of the well-known properties of nuclei, is surprisingly good.
The theoretical framework requires only eight input parameters at most: the nuclear saturation density and energy,
surface tension, the symmetry energy and its density dependence to a lesser degree, proton charge,
the spin-orbit and the nuclear pairing interaction strengths.
Some of our foremost theoretical findings are:
i) the strongly damped character of the large amplitude collective motion beyond the outer saddle-point,
ii) the fission fragment excitation energies and its sharing mechanism, and the somewhat surprising
excitation energy exchange mechanism between the fission fragments before the fission fragments are fully accelerated,
iii) the intrinsic fission fragment spins and their unexpected correlation character,
iv) the nature and the properties of the non-equilibrium neutrons emitted before the fission fragments are fully accelerated,
v) the strongly damped character of the fission fragment shape evolution after they are spatially separated,
vi) the total kinetic energy of the fission fragments,
vii) and the evolution of these properties with the initial excitation energy of the compound nucleus.
|
March 21, 2023, 10:30 |
N.V. Nikitin
(MSU, ITEP, Moscow)
|
The Bell inequalities and violation of them.
(Presentation)
Video
Abstract:
The 2022 Nobel Prize in Physics was awarded for the experimental
measurement of Bell's inequalities's violation.
This story started in the 1920's from the discussion between A. Einstein
and N. Bohr about the possibility
of reducing the quantum paradigm to the classical one. These discussion
were transferred to the experimental
area in 1964 by J. Bell using some inequality. The violation of this
inequality leads to Niels Bohr's win
in this discussion. The first experimental results appeared in 1972. Up
to the the present time the verification of the Bell inequalities violation continues.
|
March 9, 2023, 14:30 Joint Seminar HEPD - TPD |
Yu.A. Kulchitsky
(JINR)
|
Study of KNO scaling in pp-collisions at energies from 0.9 to 13 TeV using results of the ATLAS at the LHC.
(Presentation)
Video
Abstract:
The results of the study of KNO scaling in proton-proton interactions are presented at the centre-of-mass energies
from 0.9 to 13 TeV based on the ATLAS results at the LHC. A comparison with similar results of other experiments at the LHC is given.
The KNO distributions tend to be independent of energy for the highest energies.
|
March 7, 2023, 10:30 |
V.M. Mochalov
(NRC KI IPHE, Serpukhov)
|
Spin-Effect Investigation in SPASCHARM Experiment at Serpukhov Accelerator.
(Presentation)
Video
|
March 2, 2023, 14:30 Joint Seminar HEPD - TPD |
A.P. Serebrov
(PNPI NRC KI, Gatchina) |
The Neutrino-4 experiment - comparison of our result with the results of all other experiments on the search for sterile neutrinos.
HEPD-THD_Seminar_2023.03.02_Serebrov.A.P.mp4 - Video of A.P. Serebrov's speech.
|
February 28, 2023, 10:30 |
A.Yu. Voronin
(P.N. Lebedev Physical Institute of RAN, Moscow) |
Quantum states of anti-hydrogen in gravitational field and study of anti-hydrogen properties in GBAR experiment at CERN.
(GbarПИЯФSeminar.pdf)
HEPD_Seminar_Voronin_A.Yu._28.02.2023.mp4 - Video of A.Yu. Voronin's speech.
|
February 21, 2023, 10:30 |
A.V. Derbin
(PNPI NRC KI, Gatchina) |
Measurement of solar CNO neutrinos in the Borexino experiment.
(CNO_nejtrino_Derbin_seminar_HEPD_2023_v1.pdf)
HEPD_Seminar_Derbin_A.V._21.02.2023.mp4 - Video of A.V. Derbin's speech.
(Abstract - The nuclear fusion of hydrogen into helium in stars occurs, in addition to the proton-proton (pp-) chain,
which includes only hydrogen and helium isotopes, through the carbon-nitrogen-oxygen (CNO) cycle, in which
fusion is catalyzed by C, N and O nuclei. The CNO cycle produces only 1% of all solar energy and is secondary
to the Sun. However, for more massive and hotter stars, this cycle is decisive. In 2020-22 the Borexino collaboration,
which involves scientists from Russian institutes, for the first time presented the results of detection of neutrinos
emitted in the reactions of the CNO cycle on the Sun.)
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February 16, 2023, 14:30 Joint Seminar HEPD - TPD |
A.P. Serebrov
(PNPI NRC KI, Gatchina) |
The result of the Neutrino-4 experiment, sterile neutrinos and dark matter, the fourth neutrino and the Hubble constant.
HEPD-THD_Seminar_2023.02.16_Serebrov.A.P.mp4 - Video of A.P. Serebrov's speech.
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February 14, 2023, 10:30 |
V.V.Korenkov
(M.G. Mescheryakov LIT JINR, Dubna) |
Distributed and hybrid computing for Large-scale scientific projects.
(Korenkov_14.02.23_PNPI.pdf)
HEPD_Seminar_Korenkov_V.V._14.02.2023.mp4 - Video of V.V.Korenkov's speech.
(Abstract - The evolution of the global computer infrastructure for experiments at the LHC at CERN (WLCG) is presented.
Large-scale scientific projects are being implemented in Russia (PIC, NICA, SKIF, BAYKAL,SILA
),
the most important part of which is the creation of computer systems for processing experimental data.
It is necessary to create a scientific collaboration in Russia, bringing together key scientific centers
and universities participating in large-scale scientific projects.)
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February 9, 2023, 14:30 Joint Seminar HEPD - TPD |
M.G Ryskin
(PNPI NRC KI, Gatchina) |
Polarization in inclusive processes (non-perturbative effects).
(p-inc.pdf)
HEPD-THD_Seminar_2023.02.09_Ryskin.M.G.mp4 - Video of M.G Ryskin's speech.
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February 07, 2023, 10:30 |
N.P. Topchiev
(P.N. Lebedev Physical Institute, Moscow) |
High-Energy Gamma-Ray Astronomy and Current Status of the GAMMA-400.
HEPD_Seminar_Topchiev_N.P._07.02.2023.mp4 - Video of N.P. Topchiev's speech.
(Abstract - A review is presented on the study of high-energy (more than 100 MeV) gamma-ray emission on spacecraft
and ground-based facilities. Information on the development of the GAMMA-400 gamma-ray telescope for
space observatory is presented: the results of calculations of the gamma-ray telescope performance
and the results of the calibration of some gamma-ray telescope system prototypes on the positron beam
of the S-25R accelerator (Troitsk, LPI).)
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February 2, 2023, 14:30 Joint Seminar HEPD - TPD |
G.B. Safronov
(INR RAS) |
Deepwater neutrino telescope Baikal-GVD: the motivation of the experiment, the status of the detector and the latest results.
HEPD-THD_Seminar_2023.02.02_Safronov.G.B.mp4 - Video of G.B. Safronov's speech.
(Abstract - Neutrino propagates at large distances in space without trajectory bending or absorption
and thus can provide information about remote sources of high-energy particles. In 2015 a deployment of the 1 km3 -scale neutrino telescope,
Baikal-GVD, started in Lake Baikal. The experiment is focused on studies of the neutrino flux in the energy range between ~100 GeV and tens of PeV.
Presently an instrumented volume of the detector is more than 0.4 km3 thus being the largest telescope of this kind in the North Hemisphere.
In this talk we discuss the motivation of the experiment, status of the detector and the latest results.)
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January 31, 2023, 10:30 |
V.V. Koltsov
(V.G. Khlopin Radium Institute) |
Nuclear Isomers as Tool for Study of Vacuum Fluctuations Influence of Electromagnetic Field on Spontaneous Electromagnetic Transition Probability.
(Kol'tsov-seminar-2023.pdf)
HEPD_Seminar_Koltsov_V.V._31.01.2023.mp4 - Video of V.V. Koltsov's speech.
(Abstract - A review of works on studying the effect of changing the frequency spectrum of zero-point fluctuations of the electromagnetic field
inside metals on nuclear electromagnetic low energy transitions is presented.)
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January 24, 2023, 10:30 |
A.A. Dzyuba
(PNPI NRC KI, Gatchina) |
Investigation of Z boson production in pp interaction at vs=13 ÒeV in the LHCb experiment.
(2023-01-24_Dzyuba_HEPD-PNPI-Seminar_Z-at-pp.pdf)
HEPD_Seminar_Dzyuba_A.A._24.01.2023.mp4 - Video of A.A. Dzyuba's speech.
(Abstract - Results of Z boson production study for forward angles in pp interaction at vs=13 ÒeV are presented.
The measurements are performed by the LHCb experiment at LHC (CERN). The integral and differential
cross sections of Z boson production are obtained [1], angular distributions of muon pairs are studied [2],
evidence of possible charm quark contribution to the proton wave function is obtained [3].
Detection of Z boson decay muons for calibration allows to measure of the W boson mass [4].
Refs.: [1] JHEP 07 (2022) 026; [2] Phys. Rev. Lett. 129 (2022) 091801; [3] Phys. Rev. Lett. 128 (2022) 082001; [4] JHEP 01 (2022) 036.)
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January 19, 2023, 14:30 Joint Seminar HEPD - TPD |
I.I. Strakovsky
(GWU) |
Light Baryon Resonances: Restrictions and Perspectives. [The author dedicates this talk to Yakov Isaakovich Azimov].
(PNPI2023a.pdf)
HEPD-THD_Seminar_2023.01.19_Strakovsky.I.I.mp4 - Video of I.I. Strakovsky's speech.
(Abstract - The problem of nucleon resonances N' with masses below the Delta is considered. We derive bounds
for the properties of such states. Some of these are new, while others improve upon existing limits. We discuss the nature of N' states, and their unitary partners,
assuming that their existence can be verified.)
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January 17, 2023, 10:30 |
G.E. Gavrilov
(PNPI NRC KI, Gatchina) |
The Origin of Spontaneous Self-Sustaining Current in Proportional Chambers of Experiments at the LHC (According to Results of Detector Studies of the LHCb & CMS).
(2023_01_17_HEPD_seminar.pdf)
HEPD_Seminar_Gavrilov_G.E._17.01.2023.mp4 - Video of G.E. Gavrilov's speech.
(Abstract - Over the years of operation the multiwire proportional chambers in the CMS and
LHCb experiments at the LHC have shown that the only sign of their aging processes
is the appearance of spontaneous self-sustaining currents. Long-term studies have shown
that the source of these currents is the formation of unique low threshold emission nanocarbon structures.
The nature of occurrence such formations gave a hint for development of the effective methods for emission current suppression,
that today have been successfully tested on practice.)
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