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arXiv · 1811.08669

The leading hadronic contribution to the running of the Weinberg angle using covariant coordinate-space methods

Marco Cè·Antoine Gérardin·Konstantin Ottnad·Harvey B. Meyer
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Abstract

We present a preliminary study of the leading hadronic contribution to the running of the Weinberg angle $\theta_{\mathrm{W}}$. The running is extracted from the correlation function of the electromagnetic current with the vector part of the weak neutral current using both the standard time-momentum representation method and the Lorentz-covariant coordinate-space method recently introduced by Meyer. Both connected and disconnected contributions have been computed on $N_{\mathrm{f}}=2+1$ non-perturbatively $O(a)$-improved Wilson fermions configurations from the CLS initiative. Similar covariant coordinate-space methods can be used to compute the leading hadronic contribution to the anomalous magnetic moment of the muon $(g-2)_\mu$ and to the running of the QED coupling $\alpha$.

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Marco Cè, Antoine Gérardin, Konstantin Ottnad, Harvey B. Meyer. 2018-11-21. The leading hadronic contribution to the running of the Weinberg angle using covariant coordinate-space methods. https://doi.org/10.22323/1.334.0137

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