Split-even approach to the rare kaon decay $K \to π\ell^+ \ell^-$

Raoul Hodgson; Vera Gülpers; Ryan Hill; Antonin Portelli

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arXiv · 2501.18358

Split-even approach to the rare kaon decay $K \to π\ell^+ \ell^-$

Raoul Hodgson·Vera Gülpers·Ryan Hill·Antonin Portelli

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Abstract

In recent years the rare kaon decay has been computed directly at the physical point. However, this calculation is currently limited by stochastic noise stemming from a light and charm quark loop GIM subtraction. The split-even approach is an alternative estimator for such loop differences, and has shown a large variance reduction in certain quantities. We present an investigation into the use of the split-even estimator in the calculation of the rare kaon decay.

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Raoul Hodgson, Vera Gülpers, Ryan Hill, Antonin Portelli. 2025-01-30. Split-even approach to the rare kaon decay $K \to π\ell^+ \ell^-$. https://arxiv.org/abs/2501.18358

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