@Article{Hansen_etal2021,
author="Hansen, M. T.
and Romero-Lopez, F.
and Sharpe, S. R.",
title="Decay amplitudes to three hadrons from finite-volume matrix elements",
journal="Journal of High Energy Physics",
year="2021",
publisher="Springer",
volume="04",
number="4",
pages="113--44pp",
optkeywords="Lattice QCD; Kaon Physics",
abstract="We derive relations between finite-volume matrix elements and infinite-volume decay amplitudes, for processes with three spinless, degenerate and either identical or non-identical particles in the final state. This generalizes the Lellouch-Luscher relation for two-particle decays and provides a strategy for extracting three-hadron decay amplitudes using lattice QCD. Unlike for two particles, even in the simplest approximation, one must solve integral equations to obtain the physical decay amplitude, a consequence of the nontrivial finite-state interactions. We first derive the result in a simplified theory with three identical particles, and then present the generalizations needed to study phenomenologically relevant three-pion decays. The specific processes we discuss are the CP-violating K -> 3 pi weak decay, the isospin-breaking eta -> 3 pi QCD transition, and the electromagnetic gamma (*) -> 3 pi amplitudes that enter the calculation of the hadronic vacuum polarization contribution to muonic g -- 2.",
optnote="WOS:000640574400001",
optnote="exported from refbase (https://references.ific.uv.es/refbase/show.php?record=4789), last updated on Mon, 03 May 2021 07:57:59 +0000",
issn="1029-8479",
doi="10.1007/JHEP04(2021)113",
opturl="https://arxiv.org/abs/2101.10246",
opturl="https://doi.org/10.1007/JHEP04(2021)113",
language="English"
}