Pion Transition Form Factor from Twisted-Mass Lattice QCD and the Hadronic Light-by-Light ${\pi }^0$-pole Contribution to the Muon $g-2$

C. Alexandrou, S. Bacchio, G. Bergner +14

The neutral pion generates the leading pole contribution to the hadronic light-by-light tensor, which is given in terms of the nonperturbative transition form factor $\mathcal{F}_{…