Related papers: Phenomenological constraints on minimally coupled …
Lepton flavour violation has been proposed as a significant test of supersymmetric unification. Here we show that such signals are also a generic feature of supersymmetric string unified models in which there is no simple unified gauge…
The problem of testing leptogenesis from low energy experiments is discussed following three different perspectives. Firstly, we review the prospects that from low energy experiments we could reconstruct the neutrino Yukawa coupling matrix…
A minimal lepton number violation (LNV) is proposed which could naturally appear in SUSY theories, if Yukawa and LNV couplings had a common origin. According to this idea properly implemented into MSSM with an additional abelian flavor…
We investigate the possibility of having sizable effects from flavor changing neutral currents at the tree level in a particular class of Two Higgs Doublet Models. Constraints from existing experimental information are discussed. Some…
We investigate a gauge extension of the Standard Model in light of the observed hints of lepton universality violation in $b \to c \ell \nu$ and $b \to s \ell^+ \ell^-$ decays at BaBar, Belle and LHCb. The model consists of an extended…
Charged lepton flavour violation is reappraised in the context of supersymmetric see-saw mechanism. It is pointed out that a non-trivial flavour structure of right-handed neutrinos, whose effect has been thus far less studied, can give rise…
We discuss lepton flavor violation (LFV) associated with tau leptons in the general framework of the two Higgs doublet model, in which LFV couplings are introduced as a deviation from Model II Yukawa interaction. Parameters of the model are…
We consider a class of models predicting new heavy neutral fermionic states, whose mixing with the light neutrinos can be naturally significant and produce observable effects below the threshold for their production. We update the indirect…
We explore the possibility that lepton family numbers and baryon number are such good symmetries of Nature because they are the global remnant of a spontaneously broken gauge symmetry. An almost arbitrary linear combination of these…
We consider the three CP-conserving dimension-6 operators that encode the leading new-physics effects in the triple gauge couplings. The contributions to the standard-model electromagnetic dipole and semi-leptonic vector and axial-vector…
We propose renormalizable models of new physics that can explain various anomalies observed in decays of B-mesons to electron and muon pairs. The new physics states couple to linear combinations of Standard Model fermions, yielding a…
We show that the predictions for lepton flavor violating decays, in the case of quasi-degenerate neutrinos, change drastically when we include in the computation the high-energy phases present in the matrix of neutrino Yukawa couplings.
We explore the possible exotic particle content beyond the standard model by examining all its scalar bilinear combinations. We categorize these exotic scalar fields and show that without the suppression of (A) their Yukawa couplings with…
We study charged lepton flavour violation in low-scale seesaw models of minimal supergravity, which realize large neutrino Yukawa couplings thanks to approximate lepton-number symmetries. There are two dominant sources of lepton flavour…
We derive new constraints on the quantities delta_{XY}^{ij}, X,Y=L,R, which parametrise the flavour-off-diagonal terms of the charged slepton mass matrix in the MSSM. Considering mass and anomalous magnetic moment of the electron we obtain…
A realistic scheme for masses and mixing of leptons is investigated in the model with gauged SO(3) lepton flavor symmetry. Within this scheme, a nearly `bi-maximal' neutrino mixing pattern with maximal CP-violating phase is found to be the…
If one removes any \emph{ad hoc} symmetry assumptions, the general two Higgs doublet model should have additional Yukawa interactions independent from fermion mass generation, in general involving flavor changing neutral Higgs couplings.…
We investigate asymptotically safe extensions of the Standard Model with new matter fields arising in the TeV energy range. The new sector contains singlet scalars and vector-like fermions in representations which permit Yukawa interactions…
The lepton flavor violating interactions are worthwhile to examine since they are sensitive to physics beyond the Standard Model. The simplest extension of the Standard Model promoting the lepton flavor violating interactions are the so…
A plethora of ultraviolet completions of the Standard Model have extra U(1) gauge symmetries. In general, the associated massive $Z^\prime$ gauge boson can mediate flavor-changing neutral current processes at tree level. We consider a…