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arXiv · 2604.19430

An Update on the Isospin-Breaking Effects in the Pion Decay Constant with Staggered Quarks

Alessandro Cotellucci·Davide Giusti
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Abstract

We present an update on the ongoing computation of the isospin-breaking effects in the Pion Decay Constant from the BMW Collaboration. The calculation is carried out with N$_f$=2+1+1 staggered quarks with a near-physical pion mass and QED$_{\text{L}}$. We give an update on the isosymmetric value and the current determination used to compute the gradient-flow scale $w_{0}$, then we present some preliminary results of the valence-valence contribution to the axial-pseudoscalar correlator for different volumes and lattice spacings. We also discuss the next steps and plans.

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Alessandro Cotellucci, Davide Giusti. 2026-04-21. An Update on the Isospin-Breaking Effects in the Pion Decay Constant with Staggered Quarks. https://doi.org/10.22323/1.518.0235

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