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Related papers: QCD condensates and $\alpha_s$ from $e^+e^-$ and $…

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In this talk, I summarize the recent determinations in Ref.[1] of the QCD condensates and $\alpha_s$ within the SVZ expansion using the ratio of Laplace sum rule (LSR) ${\cal R}_{10}^A(\tau)$ and $\tau$-like moments ${\cal R}_{n,A},\, {\cal…

High Energy Physics - Phenomenology · Physics 2025-02-20 S. Narison , LUPM , iHEPMAD

We improve the determinations of the QCD condensates within the SVZ expansion in the axial-vector (A) channel using the ratio of Laplace sum rule (LSR) ${\cal R}_{10}^A(\tau)$ within stability criteria and $\tau$-like higher moments…

High Energy Physics - Phenomenology · Physics 2025-04-22 S. Narison

We re-examine the estimate of $\als$ and of the QCD condensates from $e^+e^-\rar I=1$ hadrons data. We conclude that $e^+e^-$ at low energies gives a value of $\Lambda$ compatible with the one from LEP and from tau inclusive decay. Using a…

High Energy Physics - Phenomenology · Physics 2011-05-05 S. Narison

Using the PDG 22 compilation of the $e^+e^-\to$ Hadrons $\oplus$ the recent CMD3 data for the pion form factor and the value of gluon condensate $<\alpha_s G^2>$ from heavy quarkonia, we extract the value of the four-quark condensate :…

High Energy Physics - Phenomenology · Physics 2024-02-27 Stephan Narison

1. I update my previous comparison of the theoretical value of the muon anomaly with the new measurement and found $\Delta a_\mu\equiv a_\mu^{exp}-a_\mu^{th} = (143\pm 42_{th}\pm 22_{exp})\times 10^{-11}$ which is about 3$\sigma$…

High Energy Physics - Phenomenology · Physics 2024-04-26 Stephan Narison

Correlations between the QCD coupling \alpha_s, the gluon condensate < \alpha_s G^2 >, and the c,b-quark running masses m_c,b in the MS-scheme are explicitly studied (for the first time) from the (axial-)vector and (pseudo)scalar charmonium…

High Energy Physics - Phenomenology · Physics 2018-12-04 Stephan Narison

The bounds on the values of gluon, four-quark and quark-gluon condensates are derived from the requirement of consistency of the sum rules for various correlators of the hybrid current $a_{\mu}=g\bar d\gamma_{\rho}\tilde G_{\rho\mu}u$. The…

High Energy Physics - Phenomenology · Physics 2009-10-28 Ketino Aladashvili , Murman Margvelashvili

In this talk, I summarize the results obtained recently in Ref.\,\cite{SNe} using the PDG 22 compilation of the $e^+e^-\to$ Hadrons $\oplus$ the recent CMD3 data for the pion form factor. Using the gluon condensate $\langle \alpha_s…

High Energy Physics - Phenomenology · Physics 2024-02-26 Stephan Narison

We re-examine recent determinations of power corrections from tau-decay and confront the results with the existing ones from QCD spectral sum rules (QSSR). We conclude that contrary to the QSSR analysis, which lead to <alpha_s…

High Energy Physics - Phenomenology · Physics 2009-04-08 Stephan Narison

We report results of our recent works [1,2] where we where the correlations between the c,b-quark running masses{m}_{c,b}, the gluon condensate<\alpha_s G^2> and the QCD coupling \alpha_s in the MS-scheme from an analysis of the charmonium…

High Energy Physics - Phenomenology · Physics 2023-08-08 Stephan Narison

The modern status of basic low energy QCD parameters is reviewed. It is demonstrated, that the recent data allows one to determine the light quark mass ratios with an accuracy 10-15%. The general analysis of vacuum condensates in QCD is…

High Energy Physics - Phenomenology · Physics 2010-04-06 B. L. Ioffe

The gluon condensate, $\langle \frac{\alpha_s}{\pi} G^2 \rangle$, i.e. the leading order power correction in the operator product expansion of current correlators in QCD at short distances, is determined from $e^+ e^-$ annihilation data in…

High Energy Physics - Phenomenology · Physics 2015-06-23 C. A. Dominguez , L. A. Hernandez , K. Schilcher

I discuss the standard SVZ-expansion of the QCD two-point correlators in terms of the QCD vacuum condensates and beyond it due to a new unflavoured 1/Q^2-term (tachyonic gluon mass squared \lambda^2) which modelizes the effects of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Stephan Narison

The problem of determination of $\alpha_{s}$ and the condensates from the moments of invariant mass distribution in the semileptonic tau decays is considered. It is investigated how the extracted values of alpha_s(m^{2}_{tau}) and the…

High Energy Physics - Phenomenology · Physics 2009-10-30 P. A. Raczka

The paper presents the short review of our to-day knowledge of vacuum condensates in QCD. The condensates are defined as vacuum averages of the operators which arise due to nonperturbative effects. The important role of condensates in…

High Energy Physics - Phenomenology · Physics 2009-11-07 B. L. Ioffe

QCD running coupling constant $\alpha_s(m_c)$ and $\alpha_s(m_b)$ are determined from heavy quarkonia $c\overline{c}$ and $b\overline{b}$ decays. The decay rates of $V\rightarrow 3g$ and $V\rightarrow e^+ e^-$ for $V=J/\psi$ and $\Upsilon$…

High Energy Physics - Phenomenology · Physics 2011-01-27 K. T. Chao , H. W. Huang , Y. Q. Liu

Using recent values of \alpha_s, the gluon condensates <\alpha_s G^2> and <g^3 f_abcG^3> and the new data on the \psi/\Upsilon-families, we update our determinations of the MS-bar running quark masses m_c,b(m_c,b) from the SVZ-Moments…

High Energy Physics - Phenomenology · Physics 2018-08-07 Stephan Narison , LUPM-CNRS-Montpellier

I present a more refined analysis of the mass-splittings between the different heavy quarkonia states, using {\it new double ratios} of exponential moments of different two-point functions. Then, I test the validity of the $1/m$-expansion,…

High Energy Physics - Phenomenology · Physics 2016-09-06 Stephan Narison

ALEPH/OPAL data on the V-A spectral functions from hadronic tau decays are used in connection with a set of Laplace transform sum rules (LSR) for fixing the size of the QCD vacuum condensates up to dimension 18. Our results favour the ones…

High Energy Physics - Phenomenology · Physics 2009-11-10 Stephan Narison

We review the determinations of the QCD coupling $\alpha_s$ from the inclusive and exclusive modes of $\tau$-decays. The most recent $\tau$-data provide the average value $ \alpha_ s \left(M^2_\tau \right)\simeq 0.347\pm 0.030 $…

High Energy Physics - Phenomenology · Physics 2012-08-27 S. Narison , :
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