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Related papers: Electron contribution to $(g-2)_\mu$ at four loops

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About 3 sigma deviation from the standard model prediction of muon anomalous magnetic moment (muon g-2) has been reported. We consider new physics beyond the standard model which has new Yukawa interactions with muon. We compute new…

High Energy Physics - Phenomenology · Physics 2015-06-05 Shunichi Kanemitsu , Kazuhiro Tobe

Recently, the contribution of positronium bound states to the electron anomalous magnetic moment was computed in Refs.[1,2]. It was argued there that this O(alpha^5) contribution is missed if electron g-2 is calculated within conventional…

High Energy Physics - Phenomenology · Physics 2014-07-23 Kirill Melnikov , Arkady Vainshtein , Mikhail Voloshin

We present the analytical results for the anomalous chromomagnetic moment of a quark at the one-loop and two-loop levels through model-independent parameterizations, considering the external gluon to be off-shell. Then, we consider…

High Energy Physics - Phenomenology · Physics 2024-04-23 Subhadip Bisal

We update our Standard Model predictions for g-2 of the muon and for the hadronic contributions to the running of the QED coupling, Delta alpha_had^(5)(M_Z^2). Particular emphasis is put on recent changes in the hadronic contributions from…

High Energy Physics - Phenomenology · Physics 2015-05-28 K. Hagiwara , R. Liao , A. D. Martin , Daisuke Nomura , T. Teubner

The recent precise measurement of the muon magnetic anomaly (g-2)_{mu} at BNL opens a window into possible new physics, provided the contribution from hadronic vacuum polarization is well understood. This talk summarizes the development in…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andreas Hocker

We report on a two-loop supersymmetric contribution to the magnetic moment (g-2)_mu of the muon which is enhanced by two powers of tan(beta). This contribution arises from a shift in the relation between the muon mass and Yukawa coupling…

High Energy Physics - Phenomenology · Physics 2009-11-13 Schedar Marchetti , Susanne Mertens , Ulrich Nierste , Dominik Stöckinger

We extend our analysis of the leading hadronic contribution to the anomalous magnetic moment of the muon using the mixed representation method to study its chiral behavior. We present results derived from local-conserved two-point lattice…

High Energy Physics - Lattice · Physics 2014-10-29 Anthony Francis , Vera Guelpers , Gregorio Herdoiza , Hanno Horch , Benjamin Jaeger , Harvey B. Meyer , Hartmut Wittig

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

In this paper we calculate the $(g-2)_{\mu}$ contribution due to a light stabilized radion using the radion couplings both to the kinetic energy and the mass term of the muon. We find that the $(g-2)_{\mu}$ contribution due to radion…

High Energy Physics - Phenomenology · Physics 2009-11-07 Prasanta Das , Uma Mahanta

This paper reports the tenth-order QED contribution to the lepton g-2 from the gauge-invariant set, called Set III(c), which consists of 390 Feynman vertex diagrams containing an internal fourth-order light-by-light-scattering subdiagram.…

High Energy Physics - Phenomenology · Physics 2013-05-30 T. Aoyama , M. Hayakawa , T. Kinoshita , M. Nio

The anomalous magnetic moments of both positive and negative muons are measured to the precision of 0.7 parts per million. Two values are in good agreement. The standard model calculations of muon g-2 are under further studies, especially…

High Energy Physics - Experiment · Physics 2007-05-23 H. Deng , for Muon g-2 Collaboration

Within the model based on the $SU (2)_L\times SU (2)_R\times U (1)_{B-L} $ gauge group and having the bidoublet and two triplets of the Higgs fields (left-right model) the Higgs sector impact on the value of the muon anomalous magnetic…

High Energy Physics - Phenomenology · Physics 2021-04-28 G. G. Boyarkina , O. M. Boyarkin

Using the momentum dependence of the dressed quark mass and the well-known formulae for the mass dependent quark-loop contribution to the light-by-light scattering insertions, we compute the hadronic light-by-light contribution to the muon…

High Energy Physics - Phenomenology · Physics 2015-11-18 Pere Masjuan , Marc Vanderhaeghen

I have evaluated up to 1100 digits of precision the contribution of the 891 4-loop Feynman diagrams contributing to the electron $g$-$2$ in QED. The total mass-independent 4-loop contribution is $ a_e =…

High Energy Physics - Phenomenology · Physics 2017-08-23 Stefano Laporta

Recently, first results were presented for two-loop corrections to the muon (g-2) from fermion/sfermion loops in the MSSM. These corrections were shown to be generally large and even logarithmically enhanced for heavy sfermions. Here, full…

High Energy Physics - Phenomenology · Physics 2015-06-17 Helvecio Fargnoli , Christoph Gnendiger , Sebastian Paßehr , Dominik Stöckinger , Hyejung Stöckinger-Kim

Quantum loops induce an anomaly, a_mu, in the magnetic moment of the muon that can be accurately measured. Its Standard Model prediction is limited in precision by contributions from hadronic vacuum polarisation of the photon. The dominant…

High Energy Physics - Phenomenology · Physics 2011-09-20 Andreas Hoecker

We comment on the theoretical uncertainties involved in estimating the hadronic effects on the light-by-light scattering contribution to the anomalous magnetic moment of the muon, especially based on the analysis and results of T.…

High Energy Physics - Phenomenology · Physics 2009-10-22 Martin B. Einhorn

We compute the leading order hadronic vacuum polarization (LO-HVP) contribution to the anomalous magnetic moment of the muon, $(g_\mu-2)$, using lattice QCD. Calculations are performed with four flavors of 4-stout-improved staggered quarks,…

We revisit the muon magnetic moment (g-2) in the context of Composite Higgs models and Technicolor, and provide general analytical expressions for computing the muon magnetic moment stemming from new fields such as, neutral gauge bosons,…

High Energy Physics - Phenomenology · Physics 2016-01-27 A. Doff , Clarissa Siqueira

In Refs. [1,2] we provided a complete dispersive evaluation of the hadronic light-by-light (HLbL) contribution to the anomalous magnetic moment of the muon. While the evaluation strategy was developed for the kinematic situation determined…

High Energy Physics - Phenomenology · Physics 2025-05-21 Martin Hoferichter , Peter Stoffer , Maximilian Zillinger