Revamped Bi-Large neutrino mixing with Gatto-Sartori-Tonin like relation

Abstract

The Gatto Sartori Tonin (GST) relation which establishes the Cabibbo angle in terms of the quark mass ratio: $\theta_{C}=\sqrt{m_d/m_s}$, is instituted as $\theta_{13}=\sqrt{m_1/m_3}$ to a Bi-large motivated lepton mixing framework that relies on the unification of mixing parameters: $\theta_{13}=\theta_{C}$ and $\theta_{12}=\theta_{23}$. This modification in addition to ruling out the possibility of vanishing $\theta_{13}$, advocates for a nonzero lowest neutrino mass and underlines the normal ordering of the neutrino masses. The framework is further enhanced by the inclusion of a charged lepton diagonalizing matrix $U_{lL}$ with $ (\theta_{12}^l \sim \theta_C, \delta=0)$. The model being architected at the Grand unification theory (GUT) scale is further run down upto the $Z$ boson scale to understand the universality of the GST relation and the Cabibbo angle.