How large are hadronic contributions to the Higgs diphoton decay?

by Uli Haisch

Monday 20 Jul 2026, 14:00 → 15:00 Europe/Zurich

4/S-030 (CERN)

In this talk we investigate whether non-perturbative QCD effects from light-quark dynamics can significantly affect the loop-induced Higgs decay into two photons. Using two complementary approaches --- dispersion relations (2510.05773) and the light-cone OPE (2512.02165) --- we find that these contributions are remarkably small. The corrections to the diphoton decay width are at the level of 10^-5, comparable to the perturbative strange-quark contribution and well below the precision expected at future Higgs facilities. Both methods lead to the same conclusion: the Standard Model prediction remains robust.

CERN26-2.pdf