arXiv subjects

A. V. Tykhonov

Publications and source records attributed to A. V. Tykhonov.

8 recordsLinked to original sources

arXiv2023

Geant4 simulation of the moderating neutrons spectrum

In this paper we deal with the problem of predicting a steady-state neutron spectrum in media of arbitrary composition and geometry. The analytical calculations of such spectrum are often too complex, if at all possible. We describe a method of Geant4-based Monte Carlo calculation of the steady-state neutron spectrum in a medium containing a fixed neutron source. In addition to the steady-state spectrum, we obtain the snapshots of the neutron spectrum evolution in time, which may be thought of as the non-equilibrium neutron spectra, and their form is of considerable interest for further studies.

physics.comp-ph↗

arXiv2017

Multi-particle field operators in quantum field theory

Using bi-spinor fields we write the pseudo-scalar and bi-spinor fields that are characterized by the field functions of coordinates of several particles, namely multi-particle fields. By applying the quantization procedure to these multi-particle fields, hadronic creation and annihilation operators have been obtained. Due to internal degrees of freedom of such hadron field, it can interact with gauge fields. This interaction is introduced by a standard derivative extension. The gauge field which was obtained in this way revealed to be a multi-particle field. We construct the dynamic equations for this multi-particle gauge field. It was shown that the solutions of these equations can describe the interaction of quarks inside hadrons and also the interaction of quarks in different hadrons via two-particle gluon field. Quanta of this two-gluon field can be considered as bound states of two gluons. These solutions describe confinement of quarks and gluons.

physics.gen-ph↗

arXiv2017

Internal States of Hadrons in Relativistic Reference Frames

The internal state of a composite particle and its transformation, when changing from the reference frame, where this composite particle is at rest, to a reference frame, where it moves relativistically, have been considered. It is supposed that the internal state of the composite particle in its rest frame can be considered in the non-relativistic approximation. This internal state is shown to remain the same, when changing from one inertial reference frame to another one. In other words, a particle that is spherically symmetric in its rest frame does not change its form in any other reference frame and does not undergo the Lorentz contraction in the direction of motion of any reference frame with respect to the rest one. A possible application of the results obtained to describe the scattering of hadrons considered as bound states of quarks has been discussed.

hep-ph↗

arXiv2014

The state of nonrelativistic quantum system in a relativistic reference frame

We consider the problem of internal particle state transformation, which is a bound state of several constituents, from the particle's rest frame to the system in which this particle is relativistic. It is assumed that in the rest frame of the composite particle, its internal state can be considered in the nonrelativistic approximation. It is shown, that this internal state is unchanged during the transition from one reference frame to another. Namely, given the particle is spherically symmetric in the rest frame, it remains spherically symmetric in any other reference frame, and does not undergo Lorentz contraction along the direction of motion of moving reference frame with respect to the rest frame. We discuss a possible application of these results to the description of hadron-hadron scattering, considering hadrons as a bound states of quarks.

hep-ph↗

arXiv2012

Gluon Loops in the Inelastic Processes in QCD

It is shown that inelastic process of the exchange with two massless gluons is formally equivalent to the process of the exchange with one massive particle. Thus, using the Laplace's method, a new mechanism of mass generation in inelastic processes is discovered, which is described by the non-Abelian gauge theory. Furthermore, it is shown that in the QCD perturbation theory, the same mechanisms of cross-sections growth take place, similar to the ones discovered before in the effective scalar theories.

hep-ph↗

arXiv2012

Mechanisms of proton-proton inelastic cross-section growth in multi-peripheral model within the framework of perturbation theory. Part 1

We demonstrate a possibility of computation of inelastic scattering cross-section in a multi-peripheral model by application of the Laplace method to multidimensional integral over the domain of physical process. The constrained maximum point of scattering cross-section integral under condition of the energy-momentum conservation has been found. In the vicinity of this point the integrand is substituted for an expression of Gaussian type, which made possible to compute this integral numerically. The paper has two parts. The hunting procedure of the constrained maximum point is considered and the properties of this maximum point are discussed in the given part of the paper. It is shown that virtuality of all internal lines of the "comb" diagram reduced at the constrained maximum point with energy growth. In the second part of the paper we give some arguments in favor of consideration of the mechanism of virtuality reduction as the mechanism of the total hadron scattering cross-section growth, which is not taken into account within the framework of Regge theory.

hep-ph↗

arXiv2012

Mechanisms of proton-proton inelastic cross-section growth in multi-peripheral model within the framework of perturbation theory. Part 2

We demonstrate a new technique for calculating proton-proton inelastic cross-section, which allows one by application of the Laplace' method replace the integrand in the integral for the scattering amplitude in the vicinity of the maximum point by expression of Gaussian type. This in turn, allows one to overcome the computational difficulties for the calculation of the integrals expressing the cross section to sufficiently large numbers of particles. We have managed to overcome these problems in calculating the proton-proton inelastic cross-section for production (n \le 8) number of secondary particles in within the framework of ϕ^3 model. As the result the obtained dependence of inelastic cross-section and total scattering cross-section on the energy \sqrt{s} are qualitative agrees with the experimental data. Such description of total cross-section behavior differs considerably from existing now description, where reggeons exchange with the intercept greater than unity is considered.

nucl-th↗

arXiv2012

Mechanisms of proton-proton inelastic cross-section growth in multi-peripheral model within the framework of perturbation theory. Part 3

We develop a new method for taking into account the interference contributions to proton-proton inelastic cross-section within the framework of the simplest multi-peripheral model based on the self-interacting scalar ϕ^3 field theory, using Laplace's method for calculation of each interference contribution. We do not know any works that adopted the interference contributions for inelastic processes. This is due to the generally adopted assumption that the main contribution to the integrals expressing the cross section makes multi-Regge domains with its characteristic strong ordering of secondary particles by rapidity. However, in this work, we find what kind of space domains makes a major contribution to the integral and these space domains are not multi-Regge. We demonstrated that because these interference contributions are significant, so they cannot be limited by a small part of them. With the help of the approximate replacement the sum of a huge number of these contributions by the integral were calculated partial cross sections for such numbers of secondary particles for which direct calculation would be impossible. The offered model qualitative agrees with experimental dependence of total scattering cross-section on energy {\sqrt s} with a characteristic minimum in the range {\sqrt s \approx 10} GeV. However, quantitative agreement was not achieved; we assume that due to the fact that we have examined the simplest diagrams of ϕ^3 theory.

hep-ph↗