In lepton-number-violating supersymmetric models, there is no natural choice of basis to distinguish the down-type Higgs and lepton superfields. We employ basis-independent techniques to identify the massless majoron and associated light scalar in the case of spontaneously-broken lepton number (L). When explicit L-violation is added, these two scalars can acquire masses of order the electroweak...

The possibility of searching in high energy e+ecollisions for a singly produced heavy lepton with an ordinary light lepton e+e+ L+t?, has been investigated. The search is motivated mainly by its distinctive experimental signatures. In a data sample corresponding to an inte grated luminosity of 30 fb-’ collected at a 1 TeV e+ecollider, the search is sensitive to a lepton of mass up to about 1 Te...

We reexamine the idea that bilinear R-parity violating couplings can be responsible for leptogenesis. We prove that, to have lepton number violation before the electroweak phase transition, misalignment between the lepton-Higgsino and slepton-Higgs sectors must be involved. The processes that generate a lepton asymmetry are bino or wino decays into a lepton-Higgs and slepton-Higgsino final stat...

We analyze muon decay using the most general local, derivative-free, Lorentz-invariant, leptonnumber-nonconserving interactions. We show that, neglecting neutrino masses, there is a one-toone correspondence between the coupling constants in the lepton-number-conserving case and combinations of coupling constants in the lepton-number-violating case; i.e., it is not possible, even in principle, t...

A three-family non-supersymmetric model with U(3)3 gauge symmetry is analyzed in the context of intersecting D-branes. This is equivalent to the ‘trinification’ model extended by three U(1) factors which survive as global symmetries in the low energy effective model. The Standard Model fermions are accommodated in the three possible bifundamental multiplets represented by strings with endpoints...

Abstract. We discuss flavour dependent lepton asymmetries in the Exceptional Supersymmetric Standard Model (E6SSM). In the E6SSM, the right-handed neutrinos do not participate in gauge interactions, and they decay into leptons and leptoquarks. Their Majorana nature allows violation of lepton number. New particles and interactions can result in substantial lepton asymmetries, even for scales as ...

Much effort has been expended in the search for new effects. These include searches for charged and neutral fundamental scalars, new families of quarks, new leptons, lepton-quark substructure, and supersymmetric particles, plus many other topics. In this report I will discuss a few of these experiments in some detail, some in a broader review, and unfortunately some not at all. For those that I...

We analyze the partial decay widths of sfermions decaying into charginos and neutralinos Γ(f̃ → f ′χ) at the one-loop level, including the electroweak and strong corrections. We present the renormalization framework, and discuss the value of the corrections. Since these corrections show non-decoupling effects, we analyze the radiative effects induced by a heavy squark sector into the lepton-slep...