Cesar Bonilla

Dirac neutrinos from flavor symmetry

We present a model where Majorana neutrino mass terms are forbidden by the flavor symmetry group Delta(27). Neutrinos are Dirac fermions and their masses arise in the same way as that of the charged fermions, due to very small Yukawa couplings. The model fits current neutrino oscillation data and correlates the octant of the atmospheric angle with the magnitude of the lightest neutrino mass, with maximal mixing excluded for any neutrino mass

Two-loop Dirac neutrino mass and WIMP dark matter

Abstract We propose a “scotogenic” mechanism relating small neutrino mass and cosmological dark matter. Neutrinos are Dirac fermions with masses arising only in two-loop order through the sector responsible for dark matter. Two triality symmetries ensure both dark matter stability and strict lepton number conservation at higher orders. A global spontaneously broken U(1) symmetry leads to a physical Diracon that induces invisible Higgs decays which add up to the Higgs to dark matter mode. This enhances sensitivities to spin-independent WIMP dark matter search below m h / 2 .

IDMS: inert dark matter model with a complex singlet

Within the Inert Doublet Model (IDM) there is a viable dark matter candidate. This simple model can provide a strong enough first order phase transition, which is required in order to account for the matter-antimatter asymmetry in the Universe (BAU). However, another necessary ingredient is missing, as there is no additional source of CP violation in the IDM, besides the standard CKM phase from the Standard Model. Additional CP violating phase can appear if a complex singlet of

Relating quarks and leptons with the T7 flavour group

SU(3)_C \times SU(2)_W \times U(1)_Y

Neutrino masses generation in a Z_4 model

with a non-zero vacuum expectation value is added to the scalar sector of the IDM. We construct the scalar potential of the inert doublet plus singlet model (IDMS), assuming an exact

Consistency of the triplet seesaw model revisited

Z_2

Vacuum stability with spontaneous violation of lepton number

symmetry, with singlet being

Neutrino mass and invisible Higgs decays at the LHC

Z_2

Naturally light neutrinos in

-even. To simplify the model we use a softly broken

Diracon

U(1)