Roberto Franceschini — Page 4

arXiv2007

Supersymmetric LHC phenomenology without a light Higgs boson

After a brief discussion of the mass of the Higgs in supersymmetry, I introduce \lambdaSUSY, a model with an extra chiral singlet superfield in addition to the MSSM field content. The key features of the model are: the superpotential W=λS H_d H_u with a large coupling λand the resulting lightest Higgs with mass above 200GeV. The main part of my contribution will be about how \lambdaSUSY manifests itself at the LHC. Discoveries of gluino, squarks and in particular of the three lightest neutral Higgs bosons are discussed.

hep-ph↗

arXiv2006

Neutrino Masses with Inverse Hierarchy from Broken L_e-L_μ-L_τ: a Reappraisal

We discuss a class of models of neutrino masses and mixings with inverse hierarchy based on a broken U(1)_F flavour symmetry with charge L_e-L_μ-L_τfor lepton doublets and arbitrary right-handed charges. The symmetry breaking sector receives separate contributions from flavon vev breaking terms and from soft mass breaking in the right handed Majorana sector. The model is able to reproduce in a natural way all observed features of the charged lepton mass spectrum and of neutrino masses and mixings (even with arbitrarily small θ_{13}), with the exception of a moderate fine tuning which is needed to accomodate the observed small value of r = Delta m^2_{sol} / Delta m^2_{atm}.

hep-ph↗