Related papers: Lepton (non-) unversality in (flavor changing) neu…
We present a search for flavor changing neutral currents in decays of top quarks. The analysis is based on a search for ttbar -> l'null + jets (l, l' = e, mu) final states using 4.1 fb^-1 of integrated luminosity of ppbar collisions at…
We summarise the most recent results of the Belle experiment about flavour changing neutral current (FCNC) radiative and (semi-) leptonic B decays. In particular, we report about the first observation of the decays B->K*l+l-, B->phi K…
Within the left-right symmetric model (LRM) the $Z$ boson decay into the channel $Z\to\tau\mu$ are investigated. The branching ratios of this decay is found in the third order of the perturbation theory. The obtained expression does not…
Decays that are highly suppressed in the standard model are excellent places to search for effects of new physics. Decays mediated by flavor-changing neutral currents are forbidden at tree level in the SM, and are often further suppressed…
We present a summary of our recent analysis update of flavour changing neutral current (FCNC) processes in the Littlest Higgs model with T-parity (LHT). The essential novelties of our update are: the removal of the logarithmic UV cutoff…
We study the decay width and forward-backward asymmetry of the lepton pair for the inclusive decay b --> s \tau^+ \tau^- in the two Higgs doublet model with three level flavor changing neutral currents (model III) and analyse the…
Here I review the status and prospects of experimental investigations into lepton flavor violation (LFV) in charged leptons. Rare LFV processes are naturally expected to occur through loops of TeV scale particles predicted by supersymmetric…
We discuss the consequences of deviations from the Standard Model observed in $b\to s\mu^+\mu^-$ transitions for flavour-changing neutral-current processes involving down-type quarks and neutrinos. We work within an effective field theory…
Recent anomalies in the decays of $B$ mesons and the Higgs boson provide hints towards lepton flavor (universality) violating physics beyond the Standard Model. We observe that four-fermion operators which can explain the $B$-physics…
We study lepton flavor violating analogs of the photoelectric effect, with a final $\mu$ or $\tau$ instead of an electron: $\gamma e\to \mu$ and $\gamma e\to \tau$. On the basis of the general parametrization of the matrix element of the…
We analyse the violations of lepton-flavour universality in the ratios B(P -> l nu)/B(P -> l' nu) using a general effective theory approach, discussing various flavour-symmetry breaking patterns of physics beyond the SM. We find that in…
We extend the Zee model by introducing a vector-like lepton doublet and a flavor dependent global $U(1)$ symmetry. Flavor changing neutral currents in the quark sector can be naturally forbidden at tree level due to the $U(1)$ symmetry,…
Flavour Changing Neutral Current (FCNC) decays are forbidden at lowest perturbative order in the Standard Model (SM) and only allowed via quantum loops. These transitions are therefore heavily suppressed in the SM, and New Physics (NP) can…
The flipped trinification, a framework for unifying the 3-3-1 and left-right symmetries, has recently been proposed in order to solve profound questions, the weak parity violation and the number of families, besides the implication for…
In view of the emerging hints for the violation of lepton flavour universality in several $B$-meson decays, we conduct a model-independent study (effective field theory approach) of several well-motivated new physics scenarios. Taking into…
We study the effect of flavor changing charged current(FCCC) of lepton sector in the hadronic tau decays, tau \to nu_X K^- pi^0 (X=e,mu). In general two Higgs doublet model, the lepton flavor changing neutral current (FCNC) arises in the…
We study the effects of an extra U(1)' gauge boson with flavor changing couplings with fermion mass eigenstates on certain B meson decays that are sensitive to such new physics contributions. In particular, we examine to what extent the…
Semileptonic Flavor Changing Neutral Current decays of charmed hadrons uniquely probe the up-sector of the Standard Model. Clean null test observables, such as CP-asymmetries, lepton-universality ratios, missing energy modes, lepton flavor…
Flavour Changing Neutral Current decays of the $B$-meson are a very useful tool for studying possible physics scenarios beyond the Standard Model (SM), where of the many FCNC modes radiative, purely leptonic and semi-leptonic decays of the…
Recently, several new experimental results of the test of lepton flavor universality (LFU) in $B\to D^{(\ast)}$ semi-leptonic decays were announced: the first result of $R_{D}$ from the LHCb Run 1 data, the first results of $R_{D}$ and…