It is shown that there is a possibility of violation of CPT symmetry in the Standard Model which does not contradict to the famous CPT theorem. To check this possibility experimentally it is necessary to increase the precision of measurements of the proton and antiproton mass difference by an order of magnitude
A low-background measurement of hafnium foil using a modified ultra-low-background high purity detector with optimized sample-to-detector geometry was performed at Laboratori Nazionale del Gran Sasso. Radiopurity of the stock Hf foil was studied in detail, in addition to an analysis of data collected over 310 day to search for rare processes that can occur in natural Hf isotopes. Firstly,...
The method of measurements of fast neutron spectra by the hydrogen recoil nuclei is well known. However, when it is used, the problem of background reactions initiated by neutrons in the detector material arises almost always.
To specify these effects we performed a simulation of two-dimensional ΔЕ2 – E spectra formed when neutrons with energies <14 MeV are detected by a telescope of...
In the color string picture with fusion and percolation
the elliptic and triangular flows are studied for p-Au and d-Au collisions at 200 GeV and 5.02 TeV. The ordering $v_n(d-Au)>v_n(p-Au)$ observed experimentally for central collisions is reproduced.The calculated elliptic flow $v_2$ at central collisions agrees satisfactorily with the data. The triangular flow $v_3$ is found to be greater...
Since 1998, experiments on the synthesis of superheavy elements (SHE) have been carried out at the Flerov Laboratory of Nuclear Reactions (FLNR) of the Joint Institute for Nuclear Research (JINR) on a gas-filled recoil separator (DGFRS). The heaviest element 294Og with Z = 118 was registered in 2002, 2005, 2012 and 2015. In all these experiments, 48Ca heavy ion beams accelerated at the...
The existing coverage of the material in the study of ink of Old Russian manuscripts was extremely insufficient to reveal their real information potential [1], in particular, in the identification of different levels of relationships between the dye and the executed text, characteristic for the manuscript culture of Old Rus'.
We propose a comprehensive approach to the laboratory studies of...
Neutron rich mercury isotopes have been studied at CERN-ISOLDE by in-source resonance ionization spectroscopy, determining the change in the mean-square charge radii of 207, 208Hg and magnetic dipole moment of 207Hg. These results reveal a doubling of the growth rate of the mean-square charge radii of mercury isotopes across the N = 126 neutron shell closure. Kinks in charge radii systematics...
Hardware-software complex was used at electrostatic tandem accelerator EGP-10 (RFNC-VNIIEF) [1] for measuring the energy and angular distributions of charged particles produced in nuclear reactions [2]. Renewal of ΔE–E telescopes and modernization of signal registration spectrometer channels were performed.
The new ΔE–E telescope developed at Ioffe Institute RAS, St.-Petersburg includes...
The dynamics of the three-nucleon system can be very extensively tested by means of the deuteron-proton breakup reaction. Experimental studies of the dp system expose various dynamical ingredients, like three-nucleon force (3NF) and Coulomb force, which play an important role in correct description of observables (e.g. cross section). It is worth to underline that experiments with polarized...
The dispersive optical model potential (DOMP) for stable Ca and Zr isotopes was found fitting to the experimental data on the nucleon scattering, single-particle properties, charge density distributions, charge root-mean square radii and neutron skin thickness for $^{40-48}$Ca and $^{90-96}$Zr isotopes. In the present study, the distorted wave Born approximation (DWBA) and the adiabatic-wave...
The reduced probabilities B{[Eλ(,Mλ); IπK(K=μ) → (IπK)'} of electro-magnetic transitions from excited states into the ground and excited states, as well as structure of low-lying states were calculated for odd-A nuclei: in the region of A=243-269 and Z=96-109. The interaction of quasiparticles and phonons was taken into account. The calculations are performed at equilibrium deformation of...
The paper presents the (n,α) reaction cross section data for zinc isotopes (64Zn and 66Zn). The work was performed at the tandem accelerator IPPE.
In the work, special attention was paid to background neutrons arising from the solid deuterium target. The background component was investigated in detail using a digital neutron spectrometer based on the organic scintillator. The thickness of the...
The new experimental investigation of the (n,γf)-reaction, neutron-induced fission after preliminary emission of gamma-rays [1], have been done in neutron resonances of U-235 in the energy range from thermal to 300 eV. The measurements of fission gamma-ray and prompt neutron multiplicities as well as energy spectra of fission gamma-rays in separated neutron resonances were carried out at the...
One of the most striking discoveries in nuclear physics made at the end of the last century was the discovery of the neutron halo in the ground states of some light nuclei located near the neutron stability boundary.
The discovery of the halo led to a revision of many existing ideas in nuclear physics. The purpose of this research is to search and study halo in isobar - analog states of light...
The Fast Interaction Trigger (FIT) [1] is one of the new detectors being constructed for the upgrade of the ALICE experiment at CERN. FIT is a thoroughly modernized design, combining the functionality of four detectors used by ALICE during LHC Run 2: the T0, V0, AD and FMD. During the upcoming LHC Run 3 and 4, in addition to the multiple triggering tasks, FIT will monitor luminosity, measure...
We calculate the cross sections for reactions of the Y-meson with light mesons. We use effective Lagrangians to calculate the production cross section and also the absorption cross section in the corresponding inverse processes. We considered a mesonic formfactor scheme for the introduction of formfactors for the SU(5) chiral meson Lagrangian approach to the Y breakup cross sections by pion...
I review the role of the Higgs boson as a unique probe of the hidden sector, which has direct implications for dark matter physics and inflation. This framework leads to specific signatures at the LHC.
The work presents calculations of the solar neutrino capture cross-section σ(E$_ν$) by $^{98,100}$Mo nuclei. In calculations experimental data on strength function S(E), received in charge-exchange reactions (p, n) [1] and ($^{3}$He, t) [2, 3] were used. Calculations of the charge-exchange strength function S(E) for these nuclei were performed as part of the self-consistent theory of finite...
We present ab initio calculations of resonances for exotic $^7$He, a nucleus with no bound states, using the realistic nucleon-nucleon interactions Daejeon16 [1] and JISP16 [2]. For this, we evaluate the $n{-}{^6\rm He}$ elastic scattering phase shifts obtained within an $S$-matrix analysis of no-core shell model results for states in the continuum (SS-HORSE-NCSM approach [3]).
Results...
Charm quark production occurs via hard scattering processes in relativistic hadron-hadron collisions and is well described by perturbative QCD down to low transverse momenta. These highly virtual quarks subsequently fragment and hadronise. Measurements of charm baryon-to-meson ratio show significant modifications in pp collisions compared to e$^+$e$^-$ [1], prompting further studies into the...
We continue our explorations [1] of the electromagnetic properties of the deuteron with help of the method of unitary clothed transformations (UCTs) [2,3]. It is the case, where one has to deal with the matrix elements $\langle \mathbf P', M'| J^{\mu}(0) | \mathbf P = \mathbf 0, M \rangle$. Here the operator $J^{\mu}(0)$ is the Nöther current density $J^{\mu}(x)$ at the point $x=0$, sandwiched...
Angular distributions of fragments from the neutron-induced fission have been measured for a number of heavy target-nuclei in the energy range 1-200 MeV at the neutron time-of-flight spectrometer GNEIS [1] based on the 1-GeV proton synchrocyclotron of the NRC “Kurchatov Institute” - PNPI (Gatchina). As a result, the anisotropy of fission fragments W(0)/W(90) deduced from the experimental data...
In the talk, it is surveyed the path how to construct the nuclear force theory starting from Quantum Chromodynamics (QCD) which is considered now as a basic theory of strong interactions in physics. Historically, since the pioneer Yukawa's work by 1935 the nuclear interactions were considered as those originated from meson exchange between nucleons (or, more generally, between baryons). But...
This is a 25 year universary for the simple multiparameter mass formula of CHIPS. The declared mean shell factors withstand for more than 25 years, whilst the number of the measured or estimated mass values is almost doubled. This formula still can be used as a prediction for the short-lived nuclei, which are produced in the high energy nuclear collisions.
$^1$ NRC “Kurchatov institute” – ITEP, Moscow, 11728, Russia;
$^2$ National Research Center “Kurchatov institute”, Moscow, 123182, Russia.
Nucleosynthesis process, supported by multiple neutron captures (r-process) is responsible for the formation in nature more than the half of all the nuclei heavier iron, and the region of its propagation on the map of nuclei lies very close to neutron...
![Fig. 1 Phonon-exchange interactions between nucleons. The rectangle means the effective interaction F of Landau-Migdal. Straight and wavy lines correspond to single-particle and phonon Green functions, circles with a wavy line stand for the amplitude of phonon production g.][1]
The phonon-exchange nuclear interactions (see Fig.1) are investigated and compared to the effective interaction...
The nuclear $^4$He + $^2$H system is of great importance to nuclear astrophysics. Radiative capture proceeding in this system is responsible for production of the $^6$Li nuclei during the primordial nucleosynthesis. In this work, the $^4$He + $^2$H radiative capture is considered from the microscopic viewpoint within a developed approach [1, 2] based on cluster aspects of nuclear structure and...
Search for dibaryon resonances in two-nucleon systems has a long history (for review see [1]). At present as one of the most realistic candidate to the dibaryon resonance is considered the $D_{IJ}=D_{03}$ peak observed by WASA@COSY [2] in the total cross section of the reaction of two-pion production $pn\to d\pi^0\pi^0$, here $I$ is the isospin and $J$ is the total angular momentum...
The Hamiltonian of the system with an additional internal degree of freedom is studied. For this purpose, the coupled channel formalism with the total Hilbert space consisting of two subspaces is used. Here, the external subspace corresponds to the relative motion of two particles and the internal one takes into account some other degrees of freedom. In the simplest case, the internal subspace...
New semi-conductor spectrometer dedicated to study of α-β-γ angular correlations in 4π-geometry was created in close cooperation between JINR and Baltic Scientific Instruments. The main part of the spectrometer is an HPGe detector that has a segmented N-area with six segments. Each of the segments has an energy resolution (FWHM) better than 1 keV for the energy 122 keV (γ– line of Co-57) and...
The study of cluster properties of various nuclear states is extremely important for nuclear physics as they are manifested at nuclear decay, fusion of colliding nuclei, reactions of knockout and transfer of clusters, etc. As in other fields of light nuclei theory ab initio approaches are actively developing for studying them. [1, 2, 3] These methods are based on solving A-nucleon Schrödinger...
Nowadays, a significant amount of the experimental data in GeV energy range was accumulated both with unpolarised and polarised beams. However, a description of the data faces problems because well developed Faddeev calculation technique cannot be applied at these energies.
In this report we consider deuteron- proton elastic scattering in the relativistic multiple scattering expansion...
The results of research on 17 bronze statues from a collection of the State Museum of Fine Arts A.S. Pushkin are presented.
The analyses of the metal elemental composition in sculptures and objects of decorative and applied art is a relatively young and rapidly developing area of scientific knowledge. This method is effective for identifying the "non-standard" alloy compositions [1]....
The motivation of the present studies is creation of the spontaneous self-supporting currents commonly denoted as Malter effect (ME) in multiwire proportional chambers used at Large Hadron Collider (LHC) beam experiments in European Organization for Nuclear Research (CERN).
Search for reasons of the origin and analysis of the nature of this effect are necessary for development of procedures...
We calculate the surface energy, the surface tension and the neutron skin thickness of the nuclear matter at all possible conditions of two-phase boundary coexistence [nuclear matter-vacuum, nuclear matter-neutron matter (after neutron drip), and nuclear matter-nuclear matter (after proton drip)]. Following [1,2], calculations are based on extended Tomas-Fermi approach. We apply a set of...
In recent decades, the issue of increasing cross sections of the thermonuclear reactions in the low-energy region has become relevant. This phenomenon is associated with the effect of the electron screening, which consists in reducing the Coulomb energy between interacting nuclei by the electrons of the surrounding substance. The study of this phenomenon is important in the astrophysics, since...
The subject of the talk is the theory of the cluster and nucleon spectroscopic factors. A mathematical proof of the necessity for taking into account the channel wave-function renormalization generated by the exchange terms of the antisymmetrization operator is given. This property was ignored in earlier approaches. Unfortunately, the ‘old” version is in use up to now through habit. The...
We study equation of state (EOS) of an accreting neutron star crust. Usually, such EOS is obtained assuming (implicitly) that the free (unbound) neutrons and nuclei in the inner crust move together. We argue, that this assumption violates the condition $\mu_n^\infty={\rm const}$, required for hydrostatic (and diffusion) equilibrium of unbound neutrons ($\mu^\infty_n$ is the redshifted neutron...
Известно, что в современных ускорительных системах (от небольших систем до циклических ускорителей) необходимо использовать достаточно сложные системы управления, которые предназначены для реализации необходимых характеристик пучка частиц. В данной статье обсуждаются методы формирования оптимальных структур пучка частиц в каналах ускорителей. Заметим, что необходимые требования к пучку могут...
Радиогеохимические методы входят в состав поисково-оценочных и разведочных работ на углеводороды, рудные тела и алмазы. Вместе с тем существуют ограничения для их более широкого применения, связанные как с особенностями геохимии урана (образование органометаллических соединений, переменная валентность и др.), так и с большими трудозатратами при исследовании изотопов радиоактивных элементов....
