arXiv subjects

O. P. Solovtsova

Publications and source records attributed to O. P. Solovtsova.

25 records · Page 2Linked to original sources

arXiv2000

Renormalization Scheme and Higher Loop Stability in Hadronic $τ$ Decay within Analytic Perturbation Theory

We apply an analytic description to the inclusive decay of the $τ$ lepton. We argue that this method gives not only a self-consistent description of the process both in the timelike region by using the initial expression for $R_τ$ and in the spacelike domain by using the analytic properties of the hadronic correlator, but also leads to the fact that theoretical uncertainties associated with unknown higher-loop contributions and renormalization scheme dependence can be reduced dramatically.

hep-ph↗

arXiv2000

Timelike and spacelike QCD characteristics of the $e^+e^-$ annihilation process

We consider the Adler $D$-function, which is defined in the spacelike region, and the $e^+e^-$ annihilation ratio smeared, according to the Poggio, Quinn, and Weinberg method, which is determined for timelike argument. We show that the method of the nonperturbative $a$-expansion allows one to describe these Euclidean and Minkowskian characteristics of the process of $e^+e^-$ annihilation down to the lowest energy scales.

hep-ph↗

arXiv1998

The Bjorken Sum Rule in the Analytic Approach to Perturbative QCD

Results of applying analytic perturbation theory (APT) to the Bjorken sum rule are presented. We study the third-order QCD correction within the analytic approach and investigate its renormalization scheme dependence. We demonstrate that, in the framework of the method, theoretical predictions of the Bjorken sum rule are, practically, scheme independent for the entire interval of momentum transfer.

hep-ph↗

arXiv1998

The Gross--Llewellyn Smith Sum Rule in the Analytic Approach to Perturbative QCD

We apply analytic perturbation theory to the Gross--Llewellyn Smith sum rule. We study the $Q^2$ evolution and the renormalization scheme dependence of the analytic three-loop QCD correction to this sum rule, and demonstrate that the results are practically renormalization scheme independent and lead to rather different $Q^2$ evolution than the standard perturbative correction possesses.

hep-ph↗

arXiv1998

Analytic Perturbative Approach to QCD

A technique called analytic perturbation theory, which respects the required analytic properties, consistent with causality, is applied to the definition of the running coupling in the timelike region, to the description of inclusive $τ$-decay, to deep-inelastic scattering sum rules, and to the investigation of the renormalization scheme ambiguity. It is shown that in the region of a few GeV the results are rather different from those obtained in the ordinary perturbative description and are practically renormalization scheme independent.

hep-ph↗

arXiv1997

Analytic Perturbation Theory and Inclusive Tau Decay

We apply analytic perturbation theory to the inclusive decay of a $τ$ lepton into hadrons. It is shown that the resulting analyticity of the coupling constant strongly influences the value of the QCD $Λ$-parameter extracted from the experimental data on $τ$ decay.

hep-ph↗

arXiv1995

Analytic Properties of the QCD Running Coupling Constant and $τ$ Decay

A non-perturbative expansion method which gives a well-defined analytic continuation of the running coupling constant from the spacelike to the timelike region is applied to the inclusive semileptonic decay of the $τ$--lepton. The method allows us to evaluate $R_τ$ by integration over the non-perturbative physical region, rather than by using Cauchy's theorem, and hence to incorporate threshold effects in a very direct way. Within our framework the difference between the effective coupling constants in the timelike and spacelike domains can be substantial and is not simply a matter of the standard $π^2$ terms.

hep-ph↗