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arXiv · 2207.14132

Distance between various discretized fermion actions

Dian-Jun Zhao·Gen Wang·Fangcheng He·Luchang Jin·Peng Sun·Yi-Bo Yang·Kuan Zhang
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Abstract

We present the leading order mixed-action effect $Δ_{\rm mix}\equiv m_{π,{\rm vs}}^2-\frac{m_{π,{\rm vv}}^2+m_{π,{\rm ss}}^2}{2}$ using HISQ, clover or overlap valence fermion actions on gauge ensembles using various sea fermion actions across a widely-used lattice spacing range $a\in [0.04,0.19]$~fm. The results suggest that $Δ_{\rm mix}$ decreases as the fourth order of the lattice spacing on the gauge ensembles with dynamical chiral sea fermions, such as Domain wall or HISQ fermions. When a clover sea fermion action which has explicit chiral symmetry breaking is used in the ensemble, $Δ_{\rm mix}$ can be much larger regardless of the valence fermion action used.

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Dian-Jun Zhao, Gen Wang, Fangcheng He, Luchang Jin, Peng Sun, Yi-Bo Yang, Kuan Zhang. 2022-11-11. Distance between various discretized fermion actions. https://doi.org/10.1103/physrevd.107.l091501

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