Related papers: On Bjorken sum rule: heavy quarks and analytic cou…
The three-loop corrections to the potential of two heavy quarks are computed. Analytic results for the most complicated master integrals are presented.
We use the QCD sum rule approach to calculate the splitting between vector and pseudoscalar mesons containing one light and one heavy quark, and the kinetic energy of the heavy quark. Our result for the splitting induced by the…
We give a short review of our recent analysis [1] of the deep inelastic scattering data (provided by BCDMS, SLAC, NMC) on F2 structure function in the non-singlet approximation with up to next-to-next-to-leading-order accuracy and analytic…
Dispersive sum rules constitute long-standing tools for extracting hadron features from QCD. We estimate the systematic uncertainties induced by assuming quark-hadron duality and improve the accuracy of the resulting predictions by…
We present a QCD sum-rule determination of the heavy-quark kinetic energy inside a heavy meson, $-\lambda_1/2 m_Q$, which is consistent with the field-theory analog of the virial theorem. We obtain $-\lambda_1\approx (0.10\pm…
We review weakly-bound heavy quarkonium systems using effective field theories of QCD. We concentrate on potential Non-Relativistic QCD, which provides with a well founded connection between QCD and descriptions of the heavy quarkonium…
The nonperturbative $Q^2$- dependence of the sum rules for the structure functions of polarized $e(\mu)N$ scattering is discussed. The determination of twist-4 corrections to the structure functions at high $Q^2$ by QCD sum rules is…
We construct the heavy baryonic currents by using the Bethe-Salpeter wave functions in the heavy quark limit. We discuss the one-loop renormalization of these heavy baryonic currents as well as their two-point correlators up to the order…
The real and imaginary part of the vacuum polarisation function $\Pi(q^2)$ induced by a massive quark is calculated in perturbative QCD up to order $\alpha_s^2$. The method is described and the results are presented. This extends the…
We present an extension of the QCD sum rule method in the external fields so as to determine the induced pseudoscalar coupling constant g_P, which tests the validity of the partially conserved axial current (PCAC) hypothesis. This is…
The improved calculation method of quark distributions in hadrons in the framework of QCD sum rules is presented. The imaginary part of the virtual photon scattering amplitude on some hadronic current is considered in the case, when initial…
The spectroscopic parameters of the heavy-light hybrid mesons with different spin-parities and different quark contents are investigated in the framework of the QCD sum rule method. The mass and current coupling of these states are…
Achievements in the heavy quark theory over the last decade are reviewed, with the main emphasis put on dynamical methods which quantify nonperturbative effects via application of the Operator Product Expansion. These include the total weak…
In the conventional QCD sum rule calculation for the $\pi NN$ coupling beyond the soft-pion limit, there are three distinct Dirac structures, each of which can be used to construct separate sum rule. We point out subtleties in the previous…
Many of the $XYZ$ resonances observed by the Belle, Babar, CLEO and BESIII collaborations in the past decade are difficult to interpret as conventional quark-antiquark mesons, motivating the consideration of scenarios such as multi-quark…
An overview of the SMC data taking and the polarized deep inelastic scattering experiment is given. The new data on the deuteron extend the kinematic range and have considerably reduced statistical and systematic errors. The evaluation of…
We demonstrate that sea quark effects of a magnitude expected from renormalization group considerations are clearly visible in the strong coupling constant measured in current full QCD simulations. Building on this result an estimate of…
We present for the first time quantitative results for the coupled dynamics of second order fluctuations in the three conserved charges of QCD based on stochastic diffusion equations for a Bjorken-type expanding hadronic medium.
Frequently, theoretical discussions of multiquark hadron states prove to be contaminated or even dominated by contributions of conventional hadrons. For the approach to QCD bound states in terms of QCD sum rules, we show how to get rid of…
Uncertainties in the next-to-leading-order calculations of heavy-quark ($Q$) production are investigated. Predictions for total cross sections, single-inclusive distributions of heavy quarks and heavy flavoured hadrons, as well as for…