# Leptogenesis in $\Delta(27)$ with a Universal Texture Zero

## TL;DR

This paper explores leptogenesis within a $ ext{Delta}(27)$ flavor model featuring a universal texture zero, demonstrating viable scenarios for generating the matter-antimatter asymmetry through right-handed neutrino decays.

## Contribution

It provides a detailed numerical analysis of leptogenesis in a $ ext{Delta}(27)$ model with a texture zero, identifying parameter regions for successful $N_1$ and $N_2$-dominated leptogenesis.

## Key findings

- Successful $N_1$-dominated leptogenesis with specific mass ranges.
- Viable $N_2$-dominated leptogenesis in a constrained parameter space.
- Lower bounds on Yukawa couplings derived from leptogenesis constraints.

## Abstract

We investigate the possibility of viable leptogenesis in an appealing $\Delta(27)$ model with a universal texture zero in the (1,1) entry. The model accommodates the mass spectrum, mixing and CP phases for both quarks and leptons and allows for grand unification. Flavoured Boltzmann equations for the lepton asymmetries are solved numerically, taking into account both $N_1$ and $N_2$ right-handed neutrino decays. The $N_1$-dominated scenario is successful and the most natural option for the model, with $M_1 \in [10^9, 10^{12}]$ GeV, and $M_1/M_2 \in [0.002, 0.1]$, which constrains the parameter space of the underlying model and yields lower bounds on the respective Yukawa couplings. Viable leptogenesis is also possible in the $N_2$-dominated scenario, with the asymmetry in the electron flavour protected from $N_1$ washout by the texture zero. However, this occurs in a region of parameter space which has a stronger mass hierarchy $M_1/M_2 < 0.002 $, and $M_2$ relatively close to $M_3$, which is not a natural expectation of the $\Delta(27)$ model.