Semileptonic $\tau$ decays: powerful probes of non-standard charged current weak interactions

Abstract

When looking for heavy ($\mathcal{O}$(few TeV)) New Physics, the most efficient way to benefit from both high and low-energy measurements simultaneously is the use of the Standard Model Effective Field Theory (SMEFT). In this talk I highlight the importance of semileptonic $\tau$ decays in complementing, in this respect, the traditional low-energy precision observables and high-energy measurements. This is yet another reason for considering hadronic tau decays as golden channels at Belle-II beyond the unquestionable interest of the CP violation anomaly in $\tau \to K_S\pi {\nu }_{\tau }$ decays, that I also discuss within the effective theory. A couple of new results for ${\tau }^{-}\to K^{-}{\nu }_{\tau }$ decays are also included.

arXiv comment7 pages. Contribution to the Proceedings of the International Workshop "e+e- Collisions From Phi to Psi 2019", held in Novosibirsk, Russia from February 25 to March 1, 2019. To be published in EPJ Web Of Conferences

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Cited by in corpus (4)

• Semileptonic tau decays beyond the Standard Model
• Effective-field theory analysis of the ${\tau }^{-}\to (K\pi {)}^{-}{\nu }_{\tau }$ decays
• CP asymmetry in $\tau \to K_S\pi {\nu }_{\tau }$ decays within the Standard Model and beyond
• $CP$ asymmetry in the angular distributions of $\tau \to K_S\pi {\nu }_{\tau }$ decays -- II: general effective field theory analysis