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Related papers: Muonium hyperfine structure and hadronic effects

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The ground state hyperfine splitting of positronium $\Delta_{\mathrm{HFS}}$ is sensitive to high order corrections of quantum electrodynamics (QED) in bound state. The theoretical prediction and the averaged experimental value for…

High Energy Physics - Experiment · Physics 2014-06-10 A. Ishida , T. Namba , S. Asai , T. Kobayashi , H. Saito , M. Yoshida , K. Tanaka , A. Yamamoto

Motivated by recent progress of theory and experiment on the anomalous magnetic moment of the electron, a_e, we update the hadronic contributions to a_e. Using our up-to-date compilation of e^+ e^- \to hadrons data, we find the leading…

High Energy Physics - Phenomenology · Physics 2015-06-11 Daisuke Nomura , Thomas Teubner

We study systematic uncertainties in the lattice QCD computation of hadronic vacuum polarization (HVP) contribution to the muon $g-2$. We investigate three systematic effects; finite volume (FV) effect, cutoff effect, and integration scheme…

High Energy Physics - Lattice · Physics 2019-09-04 Eigo Shintani , Yoshinobu Kuramashi

The ground state hyperfine splitting in positronium, $\Delta _{\mathrm{HFS}}$, is sensitive to high order corrections of QED. A new calculation up to $O(\alpha ^3)$ has revealed a $3.9 \sigma$ discrepancy between the QED prediction and the…

High Energy Physics - Experiment · Physics 2014-11-20 A. Ishida , G. Akimoto , K. Kato , T. Suehara , T. Namba , S. Asai , T. Kobayashi , H. Saito , M. Yoshida , K. Tanaka , A. Yamamoto , I. Ogawa , S. Kobayashi , T. Idehara

In this talk, I revisit and present a more comprehensive estimate of the lowest order Hadronic Vacuum Polarization (HVP) contribution $a_\mu\vert_{hvp}^{lo}$ to the muon anomalous magnetic moment (muon anomaly) from $e^+e^-\to$ Hadrons…

High Energy Physics - Phenomenology · Physics 2025-10-21 Stephan Narison

The hadronic vacuum-polarization contribution to the muon anomalous magnetic moment a_{mu}(hadr) and to the value of the eleectromagnetic coupling constant at q^2 = M^2_z are determined more precisely in connection with a new more exact…

High Energy Physics - Phenomenology · Physics 2007-05-23 B. V. Geshkenbein

We reevaluate the hadronic vacuum polarisation contributions to the muon magnetic anomaly and to the running of the electromagnetic coupling constant at the Z-boson mass. We include newest e+e- to hadrons cross-section data (among others)…

High Energy Physics - Phenomenology · Physics 2019-05-10 Michel Davier , Andreas Hoecker , Bogdan Malaescu , Zhiqing Zhang

The ground state hyperfine splitting of positronium, $\Delta_{\mathrm{HFS}}$, is sensitive to high order corrections of QED. A new calculation up to $\mathrm{O}(\alpha ^3 \ln \alpha)$ has revealed a $3.9\sigma$ discrepancy between the QED…

High Energy Physics - Experiment · Physics 2010-05-03 A. Ishida , G. Akimoto , Y. Sasaki , T. Suehara , T. Namba , S. Asai , T. Kobayashi , H. Saito , M. Yoshida , K. Tanaka , A. Yamamoto

We present a new lattice QCD calculation of the leading order hadronic vacuum polarization (LO-HVP) contribution to the muon anomalous magnetic moment $a_\mu$. We reduce uncertainties compared to our earlier computation arXiv:2002.12347 by…

On the basis of quasipotential approach to the bound state problem in QED we calculate the vacuum polarization, relativistic, recoil, structure corrections of orders $\alpha^5$ and $\alpha^6$ to the fine structure interval $\Delta…

High Energy Physics - Phenomenology · Physics 2010-12-06 E. N. Elekina , A. P. Martynenko

We use recently evaluated radiative and nonperturbative corrections to production of heavy quarks by a vector current to give very precise theoretical calculations of the high energy ($t^{1/2}\geq \sqrt{2}$ GeV) imaginary part of the photon…

High Energy Physics - Phenomenology · Physics 2007-05-23 K. Adel , F. J. Ynduráin

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 hadronic vacuum polarisation contributions to the anomalous magnetic moment of the muon, $a_{\mu}^{\rm had, VP}$ have been re-evaluated from the combination of $e^+e^-\rightarrow {\rm hadrons}$ cross section data. Focus has been placed…

High Energy Physics - Phenomenology · Physics 2018-02-21 Alexander Keshavarzi , Daisuke Nomura , Thomas Teubner

The anomalous magnetic moment of the muon $a_\mu$ is one of the most accurate quantities in Particle Physics. The long-standing discrepancy of about $3.7$ standard deviations between the experimental value and the prediction of the Standard…

High Energy Physics - Lattice · Physics 2019-10-10 Davide Giusti , Silvano Simula

The hadronic vacuum polarization (HVP) contributions to the muon $g$$-$$2$ are the crucial quantity to resolve whether new physics is present or not in the comparison between the Standard Model (SM) prediction and experimental measurements…

High Energy Physics - Phenomenology · Physics 2025-03-27 Luca Di Luzio , Alexander Keshavarzi , Antonio Masiero , Paride Paradisi

We reevaluate the hadronic contribution to the running of the QED fine structure constant alpha(s) at s = M_Z^2. We use data from e+e- annihilation and tau decays at low energy and at the qq-bar thresholds, where resonances occur. Using…

High Energy Physics - Phenomenology · Physics 2016-02-17 M. Davier , A. Hoecker

The interference effect between leptonic radiative corrections and hadronic polarization functions is calculated via optical theorem for $\mu-$pair productions. It is achieved within the use of the last data for $\sigma_h(e^+e^-\rightarrow…

High Energy Physics - Phenomenology · Physics 2017-04-07 Vladimir Sauli

The precision with which hadronic vacuum polarization (HVP) is obtained determines how accurately important observables, such as the muon anomalous magnetic moment, a_\mu, or the low-energy running of the electromagnetic coupling, \alpha,…

We present a calculation of the hadronic vacuum polarization contribution to the muon anomalous magnetic moment, $a_\mu^{\mathrm hvp}$, in lattice QCD employing dynamical up and down quarks. We focus on controlling the infrared regime of…

High Energy Physics - Lattice · Physics 2017-10-11 M. Della Morte , A. Francis , V. Gülpers , G. Herdoíza , G. von Hippel , H. Horch , B. Jäger , H. B. Meyer , A. Nyffeler , H. Wittig

On the basis of perturbation theory in fine structure constant alpha and the ratio of electron to muon masses we calculate one-loop vacuum polarization, electron vertex corrections, nuclear structure and recoil corrections to hyperfine…

High Energy Physics - Phenomenology · Physics 2015-09-01 A. P. Martynenko , A. A. Ulybin