Pion Transition Form Factor from Twisted-Mass Lattice QCD and the Hadronic Light-by-Light $π^0$-pole Contribution to the Muon $g-2$

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Alexandrou, C., Bacchio, S., Bergner, G., Burri, S., Finkenrath, J., Gasbarro, A., Hadjiyiannakou, K., Jansen, K., Kanwar, G., Kostrzewa, B., Koutsou, G., Ottnad, K., Petschlies, M., Pittler, F., Steffens, F., Urbach, C., Wenger, U.
Format: Preprint
Published: 2023
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866917557908275200
author Alexandrou, C.
Bacchio, S.
Bergner, G.
Burri, S.
Finkenrath, J.
Gasbarro, A.
Hadjiyiannakou, K.
Jansen, K.
Kanwar, G.
Kostrzewa, B.
Koutsou, G.
Ottnad, K.
Petschlies, M.
Pittler, F.
Steffens, F.
Urbach, C.
Wenger, U.
author_facet Alexandrou, C.
Bacchio, S.
Bergner, G.
Burri, S.
Finkenrath, J.
Gasbarro, A.
Hadjiyiannakou, K.
Jansen, K.
Kanwar, G.
Kostrzewa, B.
Koutsou, G.
Ottnad, K.
Petschlies, M.
Pittler, F.
Steffens, F.
Urbach, C.
Wenger, U.
contents The neutral pion generates the leading pole contribution to the hadronic light-by-light tensor, which is given in terms of the nonperturbative transition form factor $\mathcal{F}_{π^0γγ}(q_1^2,q_2^2)$. Here we present an ab-initio lattice calculation of this quantity in the continuum and at the physical point using twisted-mass lattice QCD. We report our results for the transition form factor parameterized using a model-independent conformal expansion valid for arbitrary space-like kinematics and compare it with experimental measurements of the single-virtual form factor, the two-photon decay width, and the slope parameter. We then use the transition form factors to compute the pion-pole contribution to the hadronic light-by-light scattering in the muon $g-2$, finding $a_μ^{π^0\text{-pole}} = 56.7(3.2) \times 10^{-11}$.
format Preprint
id arxiv_https___arxiv_org_abs_2308_12458
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Pion Transition Form Factor from Twisted-Mass Lattice QCD and the Hadronic Light-by-Light $π^0$-pole Contribution to the Muon $g-2$
Alexandrou, C.
Bacchio, S.
Bergner, G.
Burri, S.
Finkenrath, J.
Gasbarro, A.
Hadjiyiannakou, K.
Jansen, K.
Kanwar, G.
Kostrzewa, B.
Koutsou, G.
Ottnad, K.
Petschlies, M.
Pittler, F.
Steffens, F.
Urbach, C.
Wenger, U.
High Energy Physics - Lattice
High Energy Physics - Phenomenology
The neutral pion generates the leading pole contribution to the hadronic light-by-light tensor, which is given in terms of the nonperturbative transition form factor $\mathcal{F}_{π^0γγ}(q_1^2,q_2^2)$. Here we present an ab-initio lattice calculation of this quantity in the continuum and at the physical point using twisted-mass lattice QCD. We report our results for the transition form factor parameterized using a model-independent conformal expansion valid for arbitrary space-like kinematics and compare it with experimental measurements of the single-virtual form factor, the two-photon decay width, and the slope parameter. We then use the transition form factors to compute the pion-pole contribution to the hadronic light-by-light scattering in the muon $g-2$, finding $a_μ^{π^0\text{-pole}} = 56.7(3.2) \times 10^{-11}$.
title Pion Transition Form Factor from Twisted-Mass Lattice QCD and the Hadronic Light-by-Light $π^0$-pole Contribution to the Muon $g-2$
topic High Energy Physics - Lattice
High Energy Physics - Phenomenology
url https://arxiv.org/abs/2308.12458