An exploratory calculation of $K_{\rm L}\toμ^+μ^-$ decay from Lattice QCD at physical pion mass

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Boyle, Peter, Chao, En-Hung, Christ, Norman, Hu, Ceran, Jin, Luchang, Zhao, Yidi
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866918187194384384
author Boyle, Peter
Chao, En-Hung
Christ, Norman
Hu, Ceran
Jin, Luchang
Zhao, Yidi
author_facet Boyle, Peter
Chao, En-Hung
Christ, Norman
Hu, Ceran
Jin, Luchang
Zhao, Yidi
contents We compute the complex, long-distance two-photon-exchange amplitude which contributes to the rare $K_{\rm L}\rightarrowμ^+μ^-$ decay from lattice QCD. We use a $24^3\times 64$ physical-pion-mass gauge field ensemble at an inverse lattice spacing of $1.023$ GeV and a QED${}_\infty$-based formalism. Our implementation strategies for all five non-SU$(3)$-flavor-suppressed diagram topologies are given in detail. We achieve a 25% statistical precision on the dispersive part of this long-distance amplitude. This calculation is carried out with 2+1 quark flavors and therefore requires the addition of counter terms to compensate for the absence of the Glashow-Iliopoulos-Maiani mechanism. These counter terms are not included in the current calculation and will be the subject of a second paper. The precision of our results is limited by the reconstruction of the physical contribution of the $η$ intermediate state, for which various strategies are tested and compared.
format Preprint
id arxiv_https___arxiv_org_abs_2509_04346
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle An exploratory calculation of $K_{\rm L}\toμ^+μ^-$ decay from Lattice QCD at physical pion mass
Boyle, Peter
Chao, En-Hung
Christ, Norman
Hu, Ceran
Jin, Luchang
Zhao, Yidi
High Energy Physics - Lattice
We compute the complex, long-distance two-photon-exchange amplitude which contributes to the rare $K_{\rm L}\rightarrowμ^+μ^-$ decay from lattice QCD. We use a $24^3\times 64$ physical-pion-mass gauge field ensemble at an inverse lattice spacing of $1.023$ GeV and a QED${}_\infty$-based formalism. Our implementation strategies for all five non-SU$(3)$-flavor-suppressed diagram topologies are given in detail. We achieve a 25% statistical precision on the dispersive part of this long-distance amplitude. This calculation is carried out with 2+1 quark flavors and therefore requires the addition of counter terms to compensate for the absence of the Glashow-Iliopoulos-Maiani mechanism. These counter terms are not included in the current calculation and will be the subject of a second paper. The precision of our results is limited by the reconstruction of the physical contribution of the $η$ intermediate state, for which various strategies are tested and compared.
title An exploratory calculation of $K_{\rm L}\toμ^+μ^-$ decay from Lattice QCD at physical pion mass
topic High Energy Physics - Lattice
url https://arxiv.org/abs/2509.04346