Related papers: A Challenge to Lepton Universality in B Meson Deca…
We argue that an LHC measurement of some simple quantities related to the ratio of rates of e+mu- to e-mu+ events is surprisingly sensitive to as-yet unexcluded R-parity violating supersymmetric models with non-zero lambda-prime 231…
The leptonic decays of the tau lepton provide relevant tests on the structure of the weak currents and the universality of their couplings to the gauge bosons. The hadronic tau decay modes constitute an ideal tool for studying low--energy…
We show that by adding a single new scalar particle to the Standard Model, a TeV-scale leptoquark with the quantum numbers of a right-handed down quark, one can explain in a natural way three of the most striking anomalies of particle…
Several measurements of tree- and loop-level b-hadron decays performed in the recent years hint at a possible violation of Lepton Universality. This article presents an experimental and theoretical overview of the current status of the…
Muons are elementary particles and provide cleaner collision events that can explore higher energies compared to composite particles like protons. Muons are also far heavier than their electron cousins, meaning that they emit less…
We present recent tests of lepton universality as crucial probes of the Standard Model in semileptonic $B$-meson decays at Belle II. All presented analyses use a data sample collected at the $\Upsilon(4S)$ resonance by the Belle II…
In this talk I will present the work that we did in \cite{1}\cite{2}\cite{3}\cite{4}\cite{5} related to observed lepton universality violation by Babar, Belle and LHCb in R($D^{(*)}$) and $R_{K^{(*)}}$ as well as the reported deviation in…
We perform a global analysis of searches for the permanent electric dipole moments (EDMs) of the neutron, neutral atoms, and molecules in terms of six leptonic, semileptonic, and nonleptonic interactions involving photons, electrons, pions,…
It is proposed that $T$ violation in physics, as well as the masses of electron and $u, d$ quarks, arise from a pseudoscalar interaction with a new spin 0 field $\tau(x)$, odd in $P$ and $T$, but even in $C$. This interaction contains a…
Results are presented from a search for events containing an excited lepton (electron or muon) produced in association with an ordinary lepton of the same flavor and decaying to a lepton and two hadronic jets. Both the production and the…
We search for lepton-flavor-violating tau decays into three leptons (electron or muon) using 535 fb^{-1} of data collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. No evidence for these decays is observed and we…
Allowed charged $\pi$ meson decays are characterized by simple dynamics, few available decay channels, mainly into leptons, and extremely well controlled radiative and loop corrections. In that sense, pion decays represent a veritable…
Discrepancies between experimental measurements and Standard Model predictions in $B$-meson decays, especially in lepton flavor universality ratios like $R_{D^{(*)}}$, $R_{J/\psi}$ and branching ratios for processes like $B\to…
The large samples of tau decays available from CLEO and the four LEP experiment have resulted in new, precise measurements of the leptonic branching ratios of the $\tau$. The experimental techniques to obtain these results are reviewed with…
The $R(D^{(*)})$ puzzle stands for a $\sim3\sigma$ violation of lepton flavor universality between the decay rates of $B\to D^{(*)}\tau\nu$ and $B\to D^{(*)}\ell\nu$, where $\ell=e,\mu$. If it is accounted for by new physics, there is no…
The angular asymmetry in decays of polarized muons and tau leptons is discussed. Both the standard $V-A$ Fermi model and the general parameterization via Michel parameters are considered. Numerical importance of contributions suppressed by…
Using a sample of 122 million Upsilon(3S) decays collected with the BaBar detector at the PEP-II asymmetric energy collider at the SLAC National Accelerator Laboratory, we measure the ratio…
A next-generation rare pion decay experiment, PIONEER, is strongly motivated by several inconsistencies between Standard Model (SM) predictions and data pointing towards the potential violation of lepton flavor universality. It will probe…
The physics responsible for neutrino masses and lepton mixing remains unknown. More experimental data are needed to constrain and guide possible generalizations of the standard model of particle physics, and reveal the mechanism behind…
These proceedings review the status of New Physics contributions to flavour violating $B$ decays. The anomalies in charged and neutral current $B$ decays related to lepton flavour universality violation have received a substantial amount of…