Lattice calculation of the pion transition form factor $\pi^0 \to \gamma^* \gamma^*$
A. Gerardin*, H.B. Meyer and A. Nyffeler
Pre-published on:
December 27, 2016
Published on:
March 24, 2017
Abstract
We calculate the pion transition form factor $\FF(q_1^2,q_2^2)$, which describe the interaction of an on-shell pion with two off-shell photons, using lattice QCD simulations with two degenerate flavors of dynamical quarks. This form factor is the main ingredient in the calculation of the pion-pole contribution to hadronic light-by-light scattering in the muon $g-2$, $\amu$. We focus our study on the spacelike region with photon virtualities up to $1.5~\GeV^2$, not yet measured experimentally. Several lattice spacings and pion masses are used to extrapolate the results to the physical point and a comparison with different phenomenological models is performed. Finally, we use our extrapolated form factor to provide a lattice determinaiton of $\amu$.
DOI: https://doi.org/10.22323/1.256.0175
How to cite
Metadata are provided both in "article" format (very similar to INSPIRE) as this helps creating
very compact bibliographies which can be beneficial to authors and
readers, and in "proceeding" format
which is more detailed and complete.