Lattice QCD and the two-photon decay of the neutral pion
High Energy Physics - Lattice
2015-06-15 v1 High Energy Physics - Phenomenology
High Energy Physics - Theory
Abstract
Two-photon decays probe the structure of mesons and represent an important contribution to hadronic light-by-light scattering. For the neutral pion, the decay amplitude tests the effects of the chiral anomaly; for a heavy quarkonium state, it measures the magnitude of its wavefunction at the origin. We rederive the expression of the decay amplitude in terms of a Euclidean correlation function starting from the theory defined on the torus. The derivation shows that for timelike photons the approach to the infinite-volume decay amplitude is exponential in the periodic box size.
Keywords
Cite
@article{arxiv.1303.0138,
title = {Lattice QCD and the two-photon decay of the neutral pion},
author = {Harvey B. Meyer},
journal= {arXiv preprint arXiv:1303.0138},
year = {2015}
}
Comments
18 pages, no figures