Related papers: SU(5)-inspired double beta decay
We propose an adjoint $SU(5)$ GUT model with a $T_{7}$ family symmetry and an extra $Z_{2}\otimes Z_{3}\otimes Z_{4}\otimes Z_{4}^{\prime }\otimes Z_{12}$ discrete group, that successfully describes the prevailing Standard Model fermion…
The $\lambda$ mechanism ($W_L$-$W_R$ exchange) of the neutrinoless double beta decay ($0\nu\beta\beta$-decay), which has origin in left-right symmetric model with right-handed gauge boson at TeV scale, is investigated. The revisited…
Ever since the Majorana classic work, the nature of neutrino has been one of the central questions of the weak interaction physics. If neutrino is its own antiparticle, the immediate consequence is lepton number violation through the…
Experiments in progress may confirm a nonzero neutrinoless double beta decay rate in conflict with the cosmological upper limit on neutrino masses and thus require new physics beyond the Standard Model. A natural candidate is the Left-Right…
The radiatively induced neutrino mass matrix is investigated on the basis of an SU(5) SUSY model. In order to evade the proton decay, an ansatz based on a discrete symmetry $Z_2$ is assumed: although, at the unification scale, we have two…
A brief sketch is given of the present observational status and future prospects of the physics of neutrino mass, including a survey of the various theoretical schemes of neutrino mass generation. Emphasis is given to those which are…
The $\nu_M{\rm SM}$ is defined as the SM extended to include dimension-5 operators. In this model neutrino masses violate lepton number, and two parameters of the lepton mixing matrix, the Majorana phases, are yet to be constrained. One…
The smallness of the observed neutrino masses might have a radiative origin. Here we revisit a specific two-loop model of neutrino mass, independently proposed by Babu and Zee. We point out that current constraints from neutrino data can be…
The minimal flipped $SU(5)$ unification with the right-handed neutrino Majorana mass scale generated as a two-loop effect is arguably one of the most constrained models of perturbative baryon and lepton number violation currently on the…
In this paper we explain the 750 GeV diphoton resonance observed at the run-2 LHC as a scalar singlet $S$, that plays a key rule in generating tiny but nonzero Majorana neutrino masses. The model contains four electroweak singlets: two…
Understanding the origin of lepton number violation is one of the fundamental questions in particle physics today. Neutrinoless double beta decay provides a way in which this violation can be tested. In this article, we derive the form of…
The Standard Model of Particle Physics predicts the double-$\beta$ decay of certain nuclei with the emission of two active neutrinos. In this letter, we argue that double-$\beta$ decay experiments could be used to probe models with light…
The minimal Standard Model extension with the Weinberg operator does accommodate the observed neutrino masses and mixing, but predicts a neutrinoless double beta ($0\nu\beta\beta$) decay rate proportional to the effective electron neutrino…
It is often said that neutrino mass is a window to a new physics beyond the standard model (SM). This is certainly true if neutrinos are Majorana particles since the SM with Majorana neutrino mass is not a complete theory. The classical…
We study the models with the Majorana neutrino masses generated radiatively by two-loop diagrams due to the Yukawa $\rho \bar \ell_R^c \ell_R$ and effective $\rho^{\pm\pm} W^\mp W^\mp$ couplings along with a scalar triplet $\Delta$, where…
We propose the minimal and renormalizable non-supersymmetric top SU(5) models where the $SU(5)\times SU(3)'_C \times SU(2)'_L \times U(1)'_Y$ gauge symmetry is broken down to the Standard Model (SM) gauge symmetry at the TeV scale. The…
We study in detail the contribution of heavy composite Majorana neutrinos to neutrino-less double beta decay. Our analysis confirms the result of a previous estimate by two of the authors. Excited neutrinos couple to the electroweak gauge…
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…
We explore the neutrinoless double beta ($0\nu \beta\beta$) decay induced by an ultralight dark matter field coupled to neutrinos. The effect on $0\nu\beta\beta$ decay is significant if the coupling violates the lepton number, for which the…
We discuss the systematic decomposition of the dimension nine neutrinoless double beta decay operator, focusing on mechanisms with potentially small contributions to neutrino mass, while being accessible at the LHC. We first provide a (d=9…