A dispersive estimate of the $a_0(980)$ contribution to hadronic light-by-light scattering in $(g-2{)}_{\mu }$

Oleksandra Deineka, Igor Danilkin, Marc Vanderhaeghen

A dispersive implementation of the $a_0(980)$ resonance to $(g-2{)}_{\mu }$ requires the knowledge of the double-virtual $S$-wave ${\gamma }^{\ast }{\gamma }^{\ast }\to \pi \eta /K{\bar{K}}_{I=1}$ amplitudes. To obtain these…