Leading isospin breaking effects in the hadronic vacuum polarisation with open boundaries
Leading isospin breaking effects in the hadronic vacuum polarisation with open boundaries
We discuss leading isospin-breaking effects in the hadronic vacuum polarisation required for the investigation of the hadronic contribution to $(g-2)_{\mu}$. The calculation proceeds by expanding the relevant correlation functions around the isosymmetric limit. Isosymmetric observables are evaluated on gauge ensembles with $N_{f}=2+1$, $O(a)$ improved Wilson fermions and open boundary conditions …