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arXiv · 2604.22349

Hadronic contributions to $\alpha(Q^{2})$ and $\sin^{2}\theta_{W}(Q^{2})$ from spectral reconstruction of lattice-QCD data

Adrián del Pino·David A. Clarke·Carleton DeTar·Aida X. El-Khadra·Elvira Gámiz·Steven Gottlieb·Anthony V. Grebe·Leon Hostetler·William I. Jay·Andreas S. Kronfeld·Shaun Lahert·Jack Laiho·Michael Lynch·Andrew T. Lytle·Ethan T. Neil·Curtis T. Peterson·James N. Simone·Jacob W. Sitison·Ruth S. Van de Water·Alejandro Vaquero
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Abstract

We present preliminary results from a lattice-QCD study of the hadronic contributions to the running of the electromagnetic coupling, $\Delta\alpha(Q^2)$, and the electroweak mixing angle, $\Delta\sin^2\theta_{W}(Q^2)$. Using $N_f = 2+1+1$ HISQ ensembles at physical quark masses, we discuss the challenges posed by strong statistical correlations in the time-momentum representation and propose a spectral-reconstruction strategy to obtain controlled continuum-extrapolated results across the full energy range.

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Adrián del Pino, David A. Clarke, Carleton DeTar, Aida X. El-Khadra, Elvira Gámiz, Steven Gottlieb, Anthony V. Grebe, Leon Hostetler, William I. Jay, Andreas S. Kronfeld, Shaun Lahert, Jack Laiho, Michael Lynch, Andrew T. Lytle, Ethan T. Neil, Curtis T. Peterson, James N. Simone, Jacob W. Sitison, Ruth S. Van de Water, Alejandro Vaquero. 2026-04-24. Hadronic contributions to $\alpha(Q^{2})$ and $\sin^{2}\theta_{W}(Q^{2})$ from spectral reconstruction of lattice-QCD data. https://arxiv.org/abs/2604.22349

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