Comparison of the mixed-fermion-action Effects using different fermion and gauge actions with 2+1 and 2+1+1 flavors

Zun-Xian Zhang, Mengchu Cai, Bolun Hu +4

The leading-order low-energy constant ${\Delta }_{\mathrm{mix}}$ in mixed-action chiral perturbation theory is calculated using $2+1+1$-flavor gauge ensembles with HISQ fermions and a tadpole-i…