QCD analytic coupling
A brief overview of QCD analytic coupling is presented, mainly following the results obtained in [1]. An application to the pion-photon transition form factor is demonstrated.
hep-ph↗
arXiv subjects
I. A. Zemlyakov
Publications and source records attributed to I. A. Zemlyakov.
Pion-photon transition form factor with analytic coupling
We investigate the pion-photon transition form factor within the framework of analytic QCD. A comparison is performed between experimental data and perturbative QCD based on conventional and analytic versions of perturbation theory with the ``massive'' form of the twist-four contribution. We show that conventional perturbation theory fails to reproduce the data, while the analytic version demonstrates good agreement with experiment.
hep-ph↗
Analytic QCD: Recent Results
We present a brief overview of analytical QCD, focusing primarily on a less common form of the analytical coupling A_{\rm MA}(Q^2), which is particularly convenient for Q^2\simΛ^2. This form has been extensively used in recent studies of the (polarized) Bjorken sum rule and the Gross-Llewellyn Smith sum rule.
hep-ph↗
Gross-Llewellyn Smith sum rule with analytic coupling
We investigate the Gross-Llewellyn Smith sum rule within the framework of analytic QCD. A comparison is performed between experimental data, lattice calculations, and perturbative QCD based on conventional and analytic versions of perturbation theory with different parametrizations for the twist-four contribution. We show that conventional perturbation theory fails to reproduce the data, while the analytic version demonstrates good agreement with experiment and lattice calculations. We also discuss the relation between the Gross-Llewellyn Smith sum rule and the Bjorken sum rule.
hep-ph↗
QCD with Analytic Coupling: Recent Results
This work provides an overview of recent results obtained in the framework of QCD with analytic coupling. Applications to the polarized Bjorken and Gross-Llewellyn Smith sum rules are considered.
hep-ph↗
On Bjorken sum rule: heavy quarks and analytic coupling
We present the results of [1], where good agreement was obtained between calculations within the framework of analytic QCD and experimental data on polarized Bjorken sum rule. The heavy quark contributions are taken into account.
hep-ph↗
Heavy quark contributions in Bjorken sum rule with analytic coupling
We consider heavy quark contributions to the polarized Bjorken sum rule. We found good agreement between the experimental data and the predictions of analytic QCD. To satisfy the limit of photoproduction, we use new representation of the perturbative part of the polarized Bjorken sum rule, proposed recently.
hep-ph↗
On Bjorken sum rule with analytic coupling
We present the results of [1], where good agreement was obtained between calculations within the framework of analytic QCD and experimental data on polarized Bjorken sum rule. The photoproduction limit was also considered and a new representation of the perturbative contribution to the polarized Bjorken sum rule was obtained.
hep-ph↗
Bjorken sum rule with analytic coupling
We found good agreement between the experimental data obtained for the polarized Bjorken sum rule and the predictions of analytic QCD, as well as a strong difference between these data and the results obtained in the framework of perturbative QCD. To satisfy the limit of photoproduction and take into account Gerasimov-Drell-Hearn and Burkhardt-Cottingham sum rules, we develope new representation of the perturbative part of the polarized Bjorken sum rule.
hep-ph↗
Bjorken sum rule with analytic coupling at low Q2 values
The experimental data obtained for the polarized Bjorken sum rule Γ^{(p-n)}_1(Q^2) for small values of Q2 are approximated by the predictions obtained in the framework of analytic QCD up to the 5th order perturbation theory, whose coupling constant does not contain the Landau pole. We found an excellent agreement between the experimental data and the predictions of analytic QCD, as well as a strong difference between these data and the results obtained in the framework of standard QCD.
hep-ph↗
Fractional Analytic QCD beyond Leading Order
Fractional analytic QCD is constructed beyond leading order using the standard inverse logarithmic expansion. It is shown that, contrary to the usual QCD coupling constant, for which this expansion can be used only for large values of its argument, in the case of analytic QCD, the inverse logarithmic expansion is applicable for all values of the argument of the analytic coupling constant. We present four different views, two of which are based primarily on Polylogarithms and generalized Euler $ζ$-functions, and the other two are based on dispersion integrals. The results obtained up to the 5th order of perturbation theory, have a compact form and do not contain complex special functions that were used to solve this problem earlier. As an example, we apply our results to study the polarized Bjorken sum rule, which is currently measured very accurately.
hep-ph↗
Fractional Analytic QCD beyond Leading Order in timelike region
In this paper we show that, as in the spacelike case, the inverse logarithmic expansion is applicable for all values of the argument of the analytic coupling constant. We present two different approaches, one of which is based primarily on trigonometric functions, and the latter is based on dispersion integrals. The results obtained up to the 5th order of perturbation theory, have a compact form and their acquiring is much easier than the methods that have been used before. As an example, we apply our results to study the Higgs boson decay into a bb pair.
hep-ph↗
About Fractional Analytic QCD
We present a brief overview of fractional analytic QCD, basically following the results recently obtained in Refs. [1,2].
hep-ph↗
About Fractional Analytic QCD beyond Leading Order
We present an overview of fractional analytic QCD beyond leading order, following the results recently obtained in Ref. [1]. We demonstrate four different representations, the details of their derivation, and show the applicability of analytic QCD to the analysis of the Bjorken sum rule.
hep-ph↗