9th Plenary Workshop of the Muon g-2 Theory Initiative

Session

Lattice HLbL

Aug 6, 2026, 11:15 AM

GS117 and GS119 (Department of Physics, University of Connecticut)

26. Update on the calculation of the long-distance $\pi^0$ exchange part of the hadronic light-by-light (HLbL) contribution to muon g-2 from RBC-UKQCD.

Anton Shcherbakov (UCONN)

8/6/26, 11:15 AM

We will provide an update to the RBC-UKQCD collaborations on the lattice calculation of the position-space, long-distance $\pi^0$ exchange part of the HLbL contribution to the anomalous magnetic moment of the muon. We will present the results of the calculation from 48I and 64I gauge-field ensembles at $a^{-1}=1.73$ GeV and $a^{-1}=2.359$ GeV, respectively. Additionally, we will present the...

34. Mainz update on the HLbL

Domink Erb (Johannes Gutenberg University Mainz)

8/6/26, 11:45 AM

We present an update to the Mainz effort on the HLbL contribution to the muon $(g-2)$. We extended the number of ensembles for the calculation of the pion transition from factor $\mathcal{F}_{\pi^0 \gamma^* \gamma^*}$. This especially includes the disconnected diagrams. The form factor is the main ingredient in the calculation of the pion-pole contribution to the HLbL.
We will also show a new...

37. Towards hadronic light-by-light contribution to the muon g-2 with C* boundary conditions

Khai Phan (ETH Zurich)

8/6/26, 12:15 PM

Within the RC* programme, we are working towards an independent lattice calculation of the hadronic light-by-light (HLbL) contribution to the muon $g$-2, with $C^\star$ boundary conditions using openQxD. As a proof of concept, we compute the analogous leptonic light-by-light contribution in quenched QED at large coupling, benchmarked against the perturbative Laporta–Remiddi result, and present...

40. The hadronic light-by-light contribution to the muon $g-2$ using staggered fermions

Christian Zimmermann (University of Kentucky)

8/6/26, 2:00 PM

We calculate the hadronic light-by-light scattering contribution to the anomalous magnetic moment of the muon using staggered fermions at the physical point. This is done by evaluating four-point functions in position space using a method based on the idea by the Mainz group, which is adapted to staggered fermions. Our calculation is carried out for several physical volumes and lattice...

24. HLbL contributions from twisted-mass lattice QCD

Urs Wenger (University of Bern)

8/6/26, 2:30 PM

We present results for the hadronic light-by-light (HLbL) contribution from lattice-QCD calculations based on ETMC's Nf​=2+1+1 Wilson-clover twisted-mass ensembles at the physical point. These include continuum extrapolations for the strange- and charm-quark connected contributions and results for the light-quark connected and 2+2 disconnected contributions at two lattice spacings.