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arXiv · 2411.10379

The role of Padé and D-Log Padé approximants in the context of the MUonE Experiment

Abstract

In the context of the anomalous magnetic moment of the muon, the hadronic contribution plays a crucial role, especially given its large contribution to the final error. Currently, lattice QCD simulations are in disagreement with dispersive calculations based on $e^+e^-$ hadronic cross sections. The new MUonE experiment intends to shed light on this situation extracting the hadronic contribution to the running of the electromagnetic coupling in the space-like region, $Δα_{\rm had}(t)$, from elastic $eμ$ scattering. Still, due to the limited kinematic range that can be covered by the experiment, a powerful method must be devised to accurately extract the desired hadronic contribution from a new experiment of this type. In this work, we show how Padé and D-Log Padé approximants profiting from the analyticity of the correlator governing the hadronic contribution can be a powerful tool in reaching the required precision.

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Camilo Rojas P., Diogo Boito, Cristiane Y. London, Pere Masjuan. 2024-11-15. The role of Padé and D-Log Padé approximants in the context of the MUonE Experiment. https://arxiv.org/abs/2411.10379

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