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Title: Spectrum of heavy quarkonia in an instanton medium

Abstract

The energy-level shift in heavy-quarkonium systems that is caused by fluctuations of vacuum gluon fields is estimated by simulating these fields by an instanton liquid. The use of the corresponding vacuum correlation function makes it possible to go beyond the dipole approximation. The width of energy levels with respect to decay to e{sup +}e{sup -} pairs is also given. It is shown that, both for bottomonium and for charmonium systems, an instanton medium can ensure a scale of shifts and widths of levels that is compatible with experimental data. In particular, it is indicated that a sizable logarithmic contribution at short distances is peculiar to the instanton vacuum.

Authors:
 [1];  [2]; ;  [1]
  1. Joint Institute for Nuclear Research (Russian Federation)
  2. National Academy of Sciences of Ukraine, Bogolyubov Institute for Theoretical Physics (Ukraine)
Publication Date:
OSTI Identifier:
21075869
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Atomic Nuclei; Journal Volume: 70; Journal Issue: 5; Other Information: DOI: 10.1134/S106377880705016X; Copyright (c) 2007 Nauka/Interperiodica; Article Copyright (c) 2007 Pleiades Publishing, Ltd; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; APPROXIMATIONS; BOTTOMONIUM; CHARMONIUM; CORRELATION FUNCTIONS; DIPOLES; ELECTRONS; ENERGY LEVELS; FLUCTUATIONS; GLUONS; INSTANTONS; PARTICLE DECAY; POSITRONS; SPECTRA

Citation Formats

Dorokhov, A. E., Zinovjev, G. M., Kochelev, N. I., and Molodtsov, S. V.. Spectrum of heavy quarkonia in an instanton medium. United States: N. p., 2007. Web. doi:10.1134/S106377880705016X.
Dorokhov, A. E., Zinovjev, G. M., Kochelev, N. I., & Molodtsov, S. V.. Spectrum of heavy quarkonia in an instanton medium. United States. doi:10.1134/S106377880705016X.
Dorokhov, A. E., Zinovjev, G. M., Kochelev, N. I., and Molodtsov, S. V.. Tue . "Spectrum of heavy quarkonia in an instanton medium". United States. doi:10.1134/S106377880705016X.
@article{osti_21075869,
title = {Spectrum of heavy quarkonia in an instanton medium},
author = {Dorokhov, A. E. and Zinovjev, G. M. and Kochelev, N. I. and Molodtsov, S. V.},
abstractNote = {The energy-level shift in heavy-quarkonium systems that is caused by fluctuations of vacuum gluon fields is estimated by simulating these fields by an instanton liquid. The use of the corresponding vacuum correlation function makes it possible to go beyond the dipole approximation. The width of energy levels with respect to decay to e{sup +}e{sup -} pairs is also given. It is shown that, both for bottomonium and for charmonium systems, an instanton medium can ensure a scale of shifts and widths of levels that is compatible with experimental data. In particular, it is indicated that a sizable logarithmic contribution at short distances is peculiar to the instanton vacuum.},
doi = {10.1134/S106377880705016X},
journal = {Physics of Atomic Nuclei},
number = 5,
volume = 70,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
  • We have investigated the spectra of light-heavy quarkonia with the use of a quantum-chromodynamic potential model, which is similar to that used earlier for heavy quarkonia. An essential feature of our treatment is the inclusion of the one-loop radiative corrections to the quark-antiquark potential, which contribute significantly to the spin splitting among the quarkonium energy levels. Unlike [ital c[bar c]] and [ital b[bar b]], the potential for a light-heavy system has a complicated dependence on the light and heavy quark masses [ital m] and [ital M], and it contains a spin-orbit mixing term. We have obtained excellent results for themore » observed energy levels of [ital D][sup 0], [ital D][sub [ital s]], [ital B][sup 0], and [ital B][sub [ital s]], and we are able to provide predicted results for many unobserved energy levels. Our potential parameters for different quarkonia satisfy the constraints of quantum chromodynamics. We have also used our investigation to test the accuracy of the heavy quark effective theory. We find that the heavy quark expansion yields generally good results for the [ital B][sup 0] and [ital B][sub [ital s]] energy levels provided that [ital M][sup [minus]1] and [ital M][sup [minus]1] ln [ital M] corrections are taken into account in the quark-antiquark interactions. It does not, however, provide equally good results for the energy levels of [ital D][sup 0] and [ital D][sub [ital s]], which indicates that the effective theory cannot be applied accurately to the [ital c] quark.« less
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