The hadronic contribution to the running of the electroweak mixing angle

17 Jun 2019, 15:00
20m
Wuchang

Wuchang

Parallel Hadron structure Hadron structure

Speaker

Dr Marco Cè (Johannes Gutenberg-Universität Mainz)

Description

The electroweak mixing angle, or Weinberg angle, $\theta_{\mathrm{W}}$ is a parameter of the Standard Model that parametrizes the mixing between the electromagnetic and weak couplings.
We present a lattice study of the leading hadronic contribution to the running of $\sin^2\theta_{\mathrm{W}}$, given by the hadronic vacuum polarization (HVP) of the electromagnetic current with the vector part of the weak neutral current, estimated using the time-momentum representation (TMR) method. Both connected and disconnected contributions have been computed on $N_{\mathrm{f}}=2+1$ non-perturbatively $\mathcal{O}(a)$-improved Wilson fermions ensembles from the Coordinated Lattice Simulations (CLS) initiative. The use of different lattice spacings and quark masses allows us to reliably extrapolate the results to the physical point.

Author

Dr Marco Cè (Johannes Gutenberg-Universität Mainz)

Co-authors

Dr Antoine Gérardin (John von Neumann Institute for Computing, DESY) Hartmut Wittig Prof. Harvey B. Meyer (Cluster of Excellence PRISMA and PRISMA+ & Institut für Kernphysik & Helmholtz-Institut Mainz, Johannes Gutenberg-Universität Mainz) Jonas Wilhelm (Universität Mainz) Kohtaroh Miura (Nagoya University) Dr Konstantin Ottnad (Institut für Kernphysik, Johannes Gutenberg-Universität Mainz) Miguel Teseo San José Pérez (Johannes Gutenberg Universität)

Presentation materials