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I present a status report of the hadronic vacuum polarization effects for the muon $g-2$, to be considered as an update of [1]. The update concerns recent new inclusive $R$ measurements from KEDR in the energy range 1.84 to 3.72 GeV. For…

High Energy Physics - Phenomenology · Physics 2018-02-14 Fred Jegerlehner

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

We have completed the evaluation of all mass-dependent $\alpha^4$ QED contributions to the muon $g-2$, or $a_\mu$, in two or more different formulations. Their numerical values have been greatly improved by an extensive computer…

High Energy Physics - Phenomenology · Physics 2008-11-26 T. Kinoshita , M. Nio

This study establishes bounds on the leading-order (LO) hadronic vacuum polarization (HVP) contribution to the anomalous magnetic moment of the muon ($a_\mu^{\mathrm{HVP,LO}}$, $a_\mu = (g-2)_\mu/2$) by using H\"older's inequality and…

High Energy Physics - Phenomenology · Physics 2024-08-29 Siyuan Li , T. G. Steele , J. Ho , R. Raza , K. Williams , R. T. Kleiv

We reevaluate the hadronic contributions to the muon magnetic anomaly, and to the running of the electromagnetic coupling constant at the Z-boson mass. We include new pi+pi- cross-section data from KLOE, all available multi-hadron data from…

High Energy Physics - Phenomenology · Physics 2011-10-27 Michel Davier , Andreas Hoecker , Bogdan Malaescu , Zhiqing Zhang

Being a determination at low energies, the analysis of hadronic tau decay data provides a rather precise determination of the strong coupling alpha_s after evolving the result to M_Z. At such a level of precision, even small…

High Energy Physics - Phenomenology · Physics 2015-06-03 D. Boito , O. Cata , M. Golterman , M. Jamin , K. Maltman , J. Osborne , S. Peris

Using recently developed methods for the evaluation of five-loop amplitudes in perturbative QCD, corrections of order alpha_s^4 for the cross section of electron-positron annihilation into hadrons and for the decay rates of the Z-boson and…

High Energy Physics - Phenomenology · Physics 2008-11-26 P. A. Baikov , K. G. Chetyrkin , J. H. Kühn

We calculate the $O(\alpha_s)$ and $O(\alpha_s^2)$ gluon radiative corrections to the QCD sum rule for the first Gegenbauer moment $a_1^K$ of the kaon light-cone distribution amplitude. The NNL0 accuracy is achieved for the perturbative…

High Energy Physics - Phenomenology · Physics 2008-11-26 K. G. Chetyrkin , A. Khodjamirian , A. A. Pivovarov

Using recent results of Avdeev et al. and an expansion for $\mu_t/\mms$ ($M_t$ is the pole mass and $\mu_t\equiv \hat{m_t}(\mu_t)$ ), it is shown that when deltarho is expressed in terms of $\hat{m_t}^2(M_t)$, the QCD correction is only…

High Energy Physics - Phenomenology · Physics 2009-10-28 Alberto Sirlin

Although the methods of calculation of power corrections in QCD sum rules are well known, algebraic complexity rapidly grows with the increase of vacuum condensates' dimensions. Currently, state-of-the-art calculations include dimension 7…

High Energy Physics - Phenomenology · Physics 2010-11-01 A. G. Grozin

The anomalous magnetic moment of the muon has been measured to 0.5 ppm in a series of precision experiments at the Brookhaven Alternating Gradient Synchrotron. The individual results for each sign: a(mu+)= 11 659 204(7)(5) E-10 and a(mu-) =…

High Energy Physics - Phenomenology · Physics 2007-05-23 Priscilla Cushman

We present the final report from a series of precision measurements of the muon anomalous magnetic moment, a_mu = (g-2)/2. The details of the experimental method, apparatus, data taking, and analysis are summarized. Data obtained at…

High Energy Physics - Experiment · Physics 2012-08-27 Muon , Collaboration , : , G. W. Bennett

We summarize recently improved results for the pseudoscalar [1,2] and vector [3] meson decay constants and their ratios from QCD spectral sum rules where N2LO + estimate of the N3LO PT and power corrections up to d< 6 dimensions have been…

High Energy Physics - Phenomenology · Physics 2015-12-01 Stephan Narison

This work presents a complete re-evaluation of the hadronic vacuum polarisation contributions to the anomalous magnetic moment of the muon, $a_{\mu}^{\rm had, \, VP}$ and the hadronic contributions to the effective QED coupling at the mass…

High Energy Physics - Phenomenology · Physics 2018-07-16 Alexander Keshavarzi , Daisuke Nomura , Thomas Teubner

In the framework of the MSSM extension with local gauged baryon and lepton numbers (BLMSSM), we calculate the muon anomalous magnetic dipole moment (MDM) and lepton $(e, \mu, \tau)$ electric dipole moment (EDM), and discuss how the muon MDM…

High Energy Physics - Phenomenology · Physics 2023-03-07 Xi Wang , Shu-Min Zhao , Xin-Xin Long , Yi-Tong Wang , Tong-Tong Wang , Hai-Bin Zhang , Tai-Fu Feng , Rong-Xiang Zhang

I summarize our self-contained determinations of the lowest order hadronic contributions to the anomalous magnetic moments a_{\mu,\tau} of the muon and tau leptons, the running QED coupling \alpha(M_Z) and the muonium hyperfine splitting…

High Energy Physics - Phenomenology · Physics 2017-08-23 Stephan Narison

We discuss the QCD sum rule calculation of the heavy-quark effective theory parameters, $\lambda_E$ and $\lambda_H$, which correspond to matrix elements representing quark-gluon three-body components in the $B$-meson wavefunction. We derive…

High Energy Physics - Phenomenology · Physics 2013-12-16 Tetsuo Nishikawa , Kazuhiro Tanaka

We present a summary of the results of two recent precise calculations of the muon anomalous magnetic moment ($g_{\mu}-2$) and the electromagnetic coupling on the $Z$ ($\bar{\alpha}_{\rm Q.E.D.}(M^2_{Z})$). The main sources of uncertainty…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. F. de Trocóniz , F. J. Ynduráin

A study of perturbative QCD calculations combined with power corrections to model hadronisation effects is presented. The QCD predictions are fitted to differential distributions and mean values of event shape observables measured in e+e-…

High Energy Physics - Experiment · Physics 2009-01-07 P. A. Movilla Fernandez , S. Bethke , O. Biebel , S. Kluth

We briefly report the modern status of heavy quark sum rules (HQSR) based on stability criteria by emphasizing the recent progresses for determining the QCD parameters (alpha_s, m_{c,b} and gluon condensates)where their correlations have…

High Energy Physics - Phenomenology · Physics 2021-02-01 Stephan Narison