Conveners
Monday after lunch: LFU, HNL, LFV
- gianluca inguglia
We study the isospin-breaking and electromagnetic corrections of hadronic tau decays, which can also be utilized to extract the CKM matrix element $V_{us}$. Our analysis extends previous work by Antonelli et al. using ChPT with resonances. Our findings show the importance of these corrections in distinguishing between the $\pi^- \bar{K}^0$ and $K^- \pi^0$ modes, beyond the Low approximation....
Improved measurements of the standard model properties of the tau provide indirect searches for beyond-the-standard-model physics. The low-background samples of $e^+e^- \to \tau^+\tau^-$ events collected by Belle and Belle II allow such measurements. We present a test of the V-A structure of $\tau \to \mu \nu \nu$ decays through the determination of the Michel parameters. In addition, latest...
The low-background environment of electron-positron collisions along with the large expected sample size and a hermetic detector make Belle II a premier experiment for studying tau-lepton physics. This talk presents recent world-leading results from Belle II determinations of the tau lepton mass.
In the past few years there have been new results on the existence of Heavy Neutral Leptons (HNL) in the $\mathcal{O}$(MeV/c$^{2}$-GeV/c$^{2}$) mass range, these results are characterised by new and improved limits on the extended Pontecorvo-Maki-Nakagawa-Sakata (PMNS) matrix element, $|U_{\tau , 4}|^{2},$ which describes the mixing of some hypothetical HNL and the Standard Model (SM)...
The future Electron-Ion Collider (EIC) at Brookhaven National Laboratory, along with its primary capacity to elucidate the nuclear structure, will offer new opportunities to probe physics beyond the Standard Model coupled to the electroweak sector. Among the best-motivated examples of such new physics are new heavy-neutral leptons (HNLs), which are likely to play a key role in neutrino mass...
We present searches for the charged lepton-flavor-violating decays $\Upsilon(1S) \to \ell \ell'$ and radiative charged lepton-flavour-violating decays $\Upsilon(1S) \to \gamma \ell \ell'$ [where $\ell =e,\mu$ and $\ell'=e,\mu,\tau$] using the 158 million Υ(2S) sample collected by the Belle detector at the KEKB collider. These searches use $\Upsilon(1S)$ mesons produced in...
