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arXiv · hep-lat/0010030

$K \to ππ$ Decays with Domain Wall Fermions: Towards Physical Results

Robert D. Mawhinney
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Abstract

We are using domain wall fermions to study $K \to ππ$ matrix elements by measuring $K \to π$ and $K \to 0$ matrix elements on the lattice and employing chiral perturbation theory to relate these to the desired physical result. The residual chiral symmetry breaking of domain wall fermions with a finite extent in the fifth dimension impacts these measurements. Using the Ward-Takahashi identities, we investigate residual chiral symmetry breaking effects for divergent quantities and study pathologies of the quenched approximation for small quark mass. We then discuss the $ΔS = 1$ operator $O_2$, where chiral symmetry is vital for the subtraction of unphysical effects.

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BibTeXRIS

Robert D. Mawhinney. 2000-10-31. $K \to ππ$ Decays with Domain Wall Fermions: Towards Physical Results. https://doi.org/10.1016/s0920-5632(01)00949-5

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