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.

7 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

References in corpus (11)

• Renormalization-group evolution of new physics contributions to (semi)leptonic meson decays
• Scalar K pi form factor and light quark masses
• K pi vector form factor, dispersive constraints and tau -> nu_tau K pi decays
• K pi vector form factor constrained by tau ---> K pi nu_tau and K_l3 decays
• Non-standard semileptonic hyperon decays
• Combined analysis of the decays ${\tau }^{-}\to K_S{\pi }^{-}{\nu }_{\tau }$ and ${\tau }^{-}\to K^{-}\eta {\nu }_{\tau }$
• Effective-field theory analysis of the ${\tau }^{-}\to (K\pi {)}^{-}{\nu }_{\tau }$ decays
• Effective-field theory analysis of the ${\tau }^{-}\to {\eta }^{(\prime )}{\pi }^{-}{\nu }_{\tau }$ decays
• Supersymmetry and CP violation in |ΔS|=1 tau-decays
• Is there a paradox in CP asymmetries of tau to K_{L,S} pi nu decays?
• Tensors for tending to tensions in $\tau$ decays

Cited by in corpus (3)

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