Related papers: Non-decoupling and lepton number violation in left…
Within type-I seesaw mechanism it is possible to have large (order one) light-heavy neutrino mixing even in case of low right-handed neutrino mass scale (of the order of GeV). This implies large lepton flavor violation. As example we…
In R-parity-violating (RPV) supersymmetric models, light neutralinos with masses from the GeV-scale down to even zero are still allowed by all laboratory constraints. They are further consistent with dark matter observations, as they decay…
We investigate the effect of B+L - violating anomalous generation of massive right-handed neutrinos on their decoupling, when the right-handed neutrino mass is considerably greater than the right-handed gauge boson masses. Considering…
Very little is known about the mass spectrum of fermions in the standard model. In this talk, I point out that in the simplest extension of the standard model, in which all right-handed fields are singlets, it is quite possible that a…
In the type-I seesaw model the size of mixing between light and heavy neutrinos, nu and N, respectively, is of order the square root of their mass ratio, (m_nu/m_N)^(1/2), with only one generation of the neutrinos. Since the light-neutrino…
We point out that extensions of the Standard Model with low scale (~TeV) lepton number violation (LNV) generally lead to a pattern of lepton flavor violation (LFV) experimentally distinguishable from the one implied by models with GUT scale…
We consider the Standard Model extended by right-handed neutrinos to explain massive neutrinos through the seesaw mechanism. The new fermion can be observed when it has a sufficiently small mass and large mixings to left-handed neutrinos.…
One way to detect the presence of new particles in theories beyond the standard model is through their contribution to electroweak loop effects. We comment on the importance of a consistent inclusion of their mixing angles to ensure that…
We point out two simple but instructive possibilities to construct the charged lepton and neutrino mass matrices, from which the nearly bi-maximal neutrino mixing with large T violation can naturally emerge. The two lepton mixing scenarios…
If a fourth generation of leptons exists, both the neutrino and its charged partner must be heavier than 45 GeV. We suppose that the neutrino is the heavier of the two, and that a global or discrete symmetry prohibits intergenerational…
Gauge-mediated supersymmetry breaking is known to greatly suppress flavor changing neutral current effects. However, we show that gauge mediation in the context of leptogenesis implies potentially large lepton flavor violating signals. If…
The non-vanishing neutrino mass strongly hints the existence of right-handed neutrinos (RHNs), singlets of the standard model (SM). However, they are highly decoupled from the SM and difficult to probe. In this work, we consider the…
Deviations from unitarity in the three-neutrino mixing canonical picture are expected in many physics scenarios beyond the Standard Model. The mixing of new heavy neutral leptons with the three light neutrinos would in principle modify the…
In many models of CP violation, the electric dipole moment (EDM) of a heavy charged or neutral lepton could be very large. We present an explicit model in which a heavy neutrino EDM can be as large as $10^{-16}$ e-cm, or even a factor of…
CP violation in the lepton sector, and other aspects of neutrino physics, are studied within a high scale supersymmetry model. In addition to the sneutrino vacuum expectation values (VEVs), the heavy vector-like triplet also contributes to…
Assuming the same form of all mass matrices as motivated by quark-lepton symmetry, we discuss conditions under which bi-large mixing in the lepton sector can be obtained with a minimal amount of fine tuning requirements for possible models.…
We study the possibility of observing lepton number violation in the right-handed sneutrino sector of the Next-to-Minimal Supersymmetric Standard Model extended with right-handed neutrinos. The scalar potential introduces a lepton number…
The Large Hadron Collider has a potential to probe the scale of left-right symmetry restoration and the associated lepton number violation. Moreover, it offers hope of measuring the right-handed leptonic mixing matrix. We show how this,…
We study the inverse seesaw mechanism for neutrino masses and phenomenological consequences in the context of conformal electro-weak symmetry breaking. The main difference to the usual case is that all explicit fermion mass terms including…
Neutrino oscillation data indicate the presence of a 2-3 symmetry for the left-handed neutrinos. We show that this symmetry between the second and third generations cannot be extended to include the charged leptons, no matter what basis we…