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Related papers: Proton-box contribution to $a_{\mu}^{\rm{HLbL}}$

200 papers

We present a calculation of the hadronic vacuum polarization (HVP) tensor within the framework of Dyson--Schwinger equations. To this end we use a well-established phenomenological model for the quark-gluon interaction with parameters fixed…

High Energy Physics - Phenomenology · Physics 2011-09-28 Tobias Goecke , Christian S. Fischer , Richard Williams

A precise evaluation of the electroweak contribution to the anomalous magnetic moment of the muon requires control over all aspects of the Standard Model, ranging from Higgs physics, over multi-loop computations for bosonic and…

High Energy Physics - Phenomenology · Physics 2025-05-21 Martin Hoferichter , Jan Lüdtke , Luca Naterop , Massimiliano Procura , Peter Stoffer

The current measurement of muonic $g - 2$ disagrees with the theoretical calculation by about 3 standard deviations. Hadronic vacuum polarization (HVP) and hadronic light by light (HLbL) are the two types of processes that contribute most…

High Energy Physics - Lattice · Physics 2015-11-18 Luchang Jin , Thomas Blum , Norman Christ , Masashi Hayakawa , Taku Izubuchi , Christoph Lehner

A comprehensive as of November 2003 and evaluated data compilation on sigma_tot(e+ e- --> hadrons) was used to estimate the lowest order hadronic contribution to the muon anomalous magnetic moment. The preliminary result is a_mu(had, LO) =…

High Energy Physics - Phenomenology · Physics 2007-05-23 V. V. Ezhela , S. B. Lugovsky , O. V. Zenin

The leading-order hadronic contribution to the muon magnetic moment anomaly $a_\mu\equiv (g_\mu-2)/2$, calculated using a dispersion integral of $e^+e^-$ annihilation data and $\tau$ data, is briefly reviewed. This contribution has the…

High Energy Physics - Phenomenology · Physics 2013-12-31 Zhiqing Zhang

We present a lattice-QCD calculation of the light-quark connected contribution to window observables associated with the leading-order hadronic vacuum polarization contribution to the anomalous magnetic moment of the muon,…

Strange quark contributions to the proton magnetic moment are estimated from a consideration of baryon magnetic moment sum rules. The environment sensitivity of quark contributions to baryon moments is emphasized. Pion cloud contributions…

High Energy Physics - Phenomenology · Physics 2009-10-28 Derek B. Leinweber

Calculations based on the analytic properties of the required matrix elements allow for a wide range of applications constraining the hadronic contributions to the anomalous magnetic moment of the muon $a_\mu=(g-2)_\mu/2$, both hadronic…

High Energy Physics - Phenomenology · Physics 2024-05-15 Martin Hoferichter

With the recent interest in the measured and standard model values of the muon anomalous magnetic moment, a_mu, some confusion has arisen concerning our knowledge of the hadronic contribution to a_mu. In the dispersion integral approach to…

High Energy Physics - Phenomenology · Physics 2007-05-23 William J. Marciano , B. Lee Roberts

We present our results for the leading-order hadronic quark-connected contributions to the electron, the muon, and the tau anomalous magnetic moments obtained with four dynamical quarks. Performing the continuum limit and an analysis of…

High Energy Physics - Lattice · Physics 2014-11-06 Florian Burger , Grit Hotzel , Karl Jansen , Marcus Petschlies

The pion-pole contribution to hadronic light-by-light scattering in the anomalous magnetic moment of the muon $(g-2)_\mu$ is fully determined by the doubly-virtual pion transition form factor. Although this crucial input quantity is, in…

High Energy Physics - Phenomenology · Physics 2018-10-26 Martin Hoferichter , Bai-Long Hoid , Bastian Kubis , Stefan Leupold , Sebastian P. Schneider

We investigate restrictions on the hadronic contribution to the muon $(g-2)$ factor and to the pion electromagnetic formfactor from the analytical properties of the pion formfactor and the experimental data of the pion formfactor in the…

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

Hadronic light-by-light scattering in the anomalous magnetic moment of the muon $a_\mu$ is one of two hadronic effects limiting the precision of the Standard Model prediction for this precision observable, and hence the new-physics…

High Energy Physics - Lattice · Physics 2018-11-21 Nils Asmussen , Antoine Gérardin , Andreas Nyffeler , Harvey B. Meyer

This thesis investigates the Hadronic Light by Light (HLL) scattering contribution to the muon $g-2$, which is one of the most important low energy hadronic effects and consists mainly of the quark loop, the pion pole and the charged pion…

High Energy Physics - Phenomenology · Physics 2012-08-14 Mehran Zahiri Abyaneh

We summarize our recent new evaluation of the pion-exchange contribution to hadronic light-by-light scattering in the muon g-2. We first derive a new short-distance constraint on the off-shell pion-photon-photon form factor at the external…

High Energy Physics - Phenomenology · Physics 2014-11-20 Andreas Nyffeler

The anomalous magnetic moment of the muon, $g_\mu-2$, is one of the most promising observables to identify hints for physics beyond the Standard Model. QCD contributions are currently responsible for the largest fraction of the overall…

We employ the comparatively minimal extension of hard-wall AdS/QCD due to Katz and Schwartz which takes into account the U(1)$_A$ anomaly for computing hadronic light-by-light scattering contributions of pseudoscalar and axial vector mesons…

High Energy Physics - Phenomenology · Physics 2023-03-29 Josef Leutgeb , Jonas Mager , Anton Rebhan

We compute the charged pion loop contribution to the light-by-light scattering amplitude for off-shell photons in chiral perturbation theory through next-to-leading order (NLO). We show that NLO contributions are relatively more important…

High Energy Physics - Phenomenology · Physics 2013-05-30 Kevin T. Engel , Hiren H. Patel , Michael J. Ramsey-Musolf

We present a lattice calculation of the Euclidean position-space windows contributing to the leading-order hadronic vacuum polarization term of the muon anomalous magnetic moment $a_\mu$. Short-, intermediate- and long-distance windows are…

High Energy Physics - Lattice · Physics 2021-12-01 Davide Giusti , Silvano Simula

We report our recent lattice calculation of hadronic light-by-light contribution to muon $g-2$ using our recently developed moment method. The connected diagrams and the leading disconnected diagrams are included. The calculation is…

High Energy Physics - Lattice · Physics 2016-11-29 Luchang Jin , Thomas Blum , Norman Christ , Masashi Hayakawa , Taku Izubuchi , Chulwoo Jung , Christoph Lehner