Master Majorana neutrino mass parametrization

After introducing a master formula for the Majorana neutrino mass matrix, we present a master parametrization for the Yukawa matrices automatically in agreement with neutrino oscillation data. This parametrization can be used for any model that induces Majorana neutrino masses. The application of the master parametrization is also illustrated in an example model, with special focus on its lepton flavor violating phenomenology.

Figure 1

Neutrino mass generation in the BNT model.

Figure 2

Example points for $\mathrm{Br}(\mu \to e\gamma )$ in the BNT model as a function of the quadruplet VEV $v_{\mathrm{\Phi }}$. This figure has been obtained by allowing the neutrino oscillation parameters to vary within the $3\sigma$ ranges determined by the global fit [19], assuming normal hierarchy, $M_{\mathrm{\Psi }}$ randomly taken in the interval [0.5, 2] TeV, and $W=\mathbb{I}$. The purple points correspond to a scan in which the entries of the matrices $T$ and $K$ are randomly taken in the following ranges: $T_{ii}\in [0,2]$ and $K_{ij}$, $T_{ij}$ (with $i\ne j$) $\in [-1,1]$. The black points in the foreground correspond to a simplified scan with $T=\mathbb{I}$ and $K=0$.

Figure 3

Example contours for $\mathrm{Br}(\mu \to e\gamma )$ in the ($T_{11}$, $T_{12}$) plane for the BNT model. Neutrino oscillation parameters are taken at their best fit points according to [19], while $M_{\mathrm{\Psi }}=0.5\mathrm{TeV}$ and $v_{\mathrm{\Phi }}=10\mathrm{KeV}$ are fixed. All entries in the matrices $W$, $T$ and $K$ are taken to be trivial ($W=T=\mathbb{I}$ and $K=0$), except for $T_{11}$ and $T_{12}$, which are left as free parameters. The point in the middle of the plot [$T_{11}=1$, $T_{12}=0$] corresponds to a simplified scenario with $T=\mathbb{I}$.