arXiv subjects

U. Yakhshiev

Publications and source records attributed to U. Yakhshiev.

3 recordsLinked to original sources

arXiv2021

Gluons, Light and Heavy Quarks in the Instanton Vacuum

In this review we will concentrate on the nonperturbative effects in the properties of hadrons made from the light-heavy and heavy-heavy quarks in the framework of Instanton Liquid Model (ILM) of QCD vacuum. We briefly discuss the main features of ILM and its applicability in the heavy quark sector. The properties of gluonic systems, light and heavy quark correlators in the instanton background are also analyzed. Consideration of the both, perturbative and nonperturbative, gluon effects in the instanton background for the single heavy quark will lead to the mass shift due to the direct-instanton nonperturbative and ILM modified perturbative contributions, respectively. For the interacting heavy quark-antiquarks, the potential consists the direct instanton induced part and the one-gluon exchange (OGE) perturbative part. OGE interactions are screened at large distances due to the nonperturbative dynamics. We discuss the estimations of instanton contributions in the phenomenological Cornell type potential model. As related to the experimental data we discuss the charmonium properties and the role of instanton effects in their spectra and transitions. We discuss also the main features of heavy-light quarks systems in the ILM. As an example, it is considering the process of pions emission by exited heavy quarkonium states.

hep-ph↗

arXiv2017

Instanton effects on the heavy-quark static potential

We investigate the instanton effects on the heavy-quark potential,including its spin-dependent part, based on the instanton liquid model. Starting with the central potential derived from the instanton vacuum, we obtain the spin-dependent part of the heavy-quark potential. We discuss the results of the heavy-quark potential from the instanton vacuum. We finally solve the nonrelativistic two-body problem, associating with the heavy-quark potential from the instanton vacuum. The instanton effects on the quarkonia spectra are marginal but are required for quantitative description of the spectra.

hep-ph↗

arXiv1999

The nucleon-nucleon interaction and properties of the nucleon in a $πρω$ soliton model including a dilaton field with anomalous dimension

We investigate an extended chiral soliton model which includes $π, ρ, ω$ and $σ$ mesons as explicit degrees of freedom. The Lagrangian incorporates chiral symmetry and broken scale invariance. A scalar-isoscalar meson $σ$ is associated with a quarkonium dilaton field with a mass $\msig\approx 550 $MeV. We show that the scalar field with anomalous dimension slightly changes the static and electromagnetic properties of the nucleon. In contrast, it plays a significant role in nucleon-nucleon dynamics and gives an opportunity to describe well the two-nucleon interaction.

nucl-th↗