PoS - Proceedings of Science
Volume 385 - 10th International Workshop on Charm Physics (CHARM2020) - Parallel programme
Isospin-breaking corrections to $\tau \to \pi \pi \nu_\tau$ decays and the muon $g-2$
J.A. Miranda Hernández
Full text: pdf
Pre-published on: September 13, 2021
Published on: November 10, 2021
We review the isospin-breaking and electromagnetic corrections to the $\tau^- \to \pi^- \pi^0 \nu_\tau$ decays, which are used as an input to the two-pion contributions to the hadronic vacuum polarization (at LO) of the anomalous magnetic moment ($a_\mu$). We extend previous analyses by Cirigliano et al. working with ChPT with resonances. As an outcome, we improve the agreement between this determination and the other based on $e^+e^-$ data. The new results are in better agreement with an old estimation that uses Vector Dominance Model (VMD), and the discrepancy between the SM prediction and the combined results from BNL and FNAL is reduced to $2.1\,\sigma$ at $\mathcal{O}(p^4)$ and $2.3\sigma$ at $\mathcal{O}(p^6)$.
DOI: https://doi.org/10.22323/1.385.0043
How to cite

Metadata are provided both in "article" format (very similar to INSPIRE) as this helps creating very compact bibliographies which can be beneficial to authors and readers, and in "proceeding" format which is more detailed and complete.

Open Access
Creative Commons LicenseCopyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.