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Issue 3, 2017

Physics of nuclei and elementary particles

Microscopic description of multipole resonances in nuclear excitations’ cross sections

Microscopic description of multipole resonances in nuclear excitations’ cross sections

N. G. Goncharova

Memoirs of the Faculty of Physics 2017. N 3.

The microscopic description of multipole resonances’ fragmentation represents a challenge to nuclear theory. The results of a “particle-core coupling” version of multiparticle shell model for resonances of various multipolarity are discussed. Influence on resonance structure the distribution of hole on the states of daughter nuclei is shown; the problem of deep levels splitting is discussed. The impact of spin- and orbital currents interference on the multipole resonances’ wave functions is demonstrated

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Influence of models of the atomic nuclei on the estimated cross sections of photoneutron reactions on $^{116}$Sn

Influence of models of the atomic nuclei on the estimated cross sections of photoneutron reactions on $^{116}$Sn

A. A. Kuznetsov$^1$, V. V. Varlamov$^1$, B. S. Ishkhanov$^{1,2}$, V. N. Orlin$^1$, A. A. Prosnyakov$^2$

Memoirs of the Faculty of Physics 2017. N 3.

In this work were obtained estimated cross sections of photoneutron reactions on $^{116}$Sn based on the theoretical-experimental approach. Calculations of the used multiplicity transition fuctions were based on the calculations of combined model of photonucleon reactions and the TALYS program. The Influence of the parameters of selected models on the estimated cross sections of the reactions was evaluated.

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Gas detectors for particle identification at high energy

Gas detectors for particle identification at high energy

O. V. Meshkov, L. N. Smirnova

Memoirs of the Faculty of Physics 2017. N 3.

The paper presents briefly the evolution of gas detectors from counters to modern microstrip and pixel gas detectors. The ability to identify particles by ionization and transition radiation is shown using the transition radiation tracker detector in ATLAS experiment. The transition radiation detector of the ALICE experiment is described with a different design. Examples of microstrip gas detectors for usage ATLAS and CMS upgrade are presented.

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Teaching methods

About a possible violation of causality as an alternative to the information interpretation of quantum theory

About a possible violation of causality as an alternative to the information interpretation of quantum theory

A. V. Belinsky

Memoirs of the Faculty of Physics 2017. N 3.

This is a review of a very interesting (in the authors' view) phenomenon, the operation of the nonlinear light beam splitter. The beam splitter is a flat interface between two transparent dielectrics, at least one of which exhibits Kerr nonlinearity, i.e., its refractive index depends on the transmitted radiation intensity. Interestingly, quantum and classical theories make directly opposite predictions about the phase fluctuation of the output radiation of this device. Even more interesting is the interpretation of the quantum results, which is reduced to the alternative: either the finding of a violation of the principle of causality in the sense of the impact of events subsequent to the previous or appeal to the information interpretation of quantum theory.

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Physics of nuclei and elementary particles

Features of the formation and decay of transuranium nuclei formed in reactions with heavy ions

Features of the formation and decay of transuranium nuclei formed in reactions with heavy ions

D. O. Eremenko$^{1,2}$, D. I. Denisova$^1$, V. A. Drozdov$^2$, S. Yu. Platonov$^{1,2}$, O. V. Fotina$^{2,3}$, O. A. Yuminov$^2$

Memoirs of the Faculty of Physics 2017. N 3.

The features of the processes of formation and decay of transuranium nuclei formed in the reactions of complete fusion of heavy ions are analyzed. When analyzing the experimental data for the $^{16}$O+$^{232}$Th, we used quantum-mechanical calculations of the initial distributions for the components of the total angular momentum of the compound nuclei $^{248,247}$Cf and the dynamic ssion model to describe their decay. It is shown that the eects of <<memory>>on the characteristics of the entrance channel of a reaction associated with the presence of spins and deformations in colliding nuclei play an important role in the formation of angular distributions of ssion fragments.

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Energy dependence of differential cross sections for particle production at the LHC

Energy dependence of differential cross sections for particle production at the LHC

I. I. Ovcharov$^2$, L. N. Smirnova$^{1,2}$

Memoirs of the Faculty of Physics 2017. N 3.

Analysis of differential spectra of charged particles produced in proton collisions at the center of mass energies √s = 0.9, 2.36, 7, 8 и 13 TeV in dependence on transverse momentum at the LHC is presented. The parameterization of both transverse momentum spectra and their ratios are fulfilled. It is shown that particle spectrum on transverse momentum becomes harder with increase of proton collision energy.

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Energy dependence of differential jet cross sections in the ATLAS experiment at the LHC

Energy dependence of differential jet cross sections in the ATLAS experiment at the LHC

I. P. Mordovetc, L. N. Smirnova

Memoirs of the Faculty of Physics 2017. N 3.

In this paper we analyze the energy dependence of the differential cross sections of jets by analyzing the ratio of the differential cross sections of hadronic jets in proton collisions at energies √s = 2.76 TeV and √s = 7 TeV, measured in the ATLAS experiment at the Large Hadron Collider. The differential cross sections are approximated as a function of the transverse momentum for different values of the rapidity of the jet and their ratio by power functions. It is shown that the differential cross sections grow faster with an increase in the transverse momentum of the jet, and this effect is more pronounced when the rapidity of the jet is increased.

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Physics of Earth, atmosphere, and hydrosphere

The relationship between the acceleration of seismic movements of the bottom and variations of bottom pressure

The relationship between the acceleration of seismic movements of the bottom and variations of bottom pressure

V. A. Karpov$^1$, K. A. Sementsov$^1$, H. H. Matsumoto$^2$, Y. Y. Kaneda$^3$

Memoirs of the Faculty of Physics 2017. N 3.

According to the data of deepwater DONET observatories, the relationship between the bottom pressure variations and the acceleration of the bottom fluctuations during the Tohoku 2011 earthquake was investigated. The method of cross-spectral analysis confirmed the existence of a linear relationship between the pressure variations and the vertical acceleration component in the <<forced oscillation>> frequency range. The connection is manifested as a close to unity value of the square of the coherence at practically zero phase shift. It is shown that the slight deviations from this rule observed for some stations are related to the contribution to variation in the pressure of the horizontal oscillations of nearby underwater slopes.

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