Leptogenesis in a $\Delta(27) \times SO(10)$ SUSY GUT

Understand

Although $SO(10)$ Supersymmetric (SUSY) Grand Unification Theories (GUTs) are very attractive for neutrino mass and mixing, it is often quite difficult to achieve successful leptogenesis from the lightest right-handed neutrino $N_1$ due to the strong relations between neutrino and up-type quark Yukawa couplings.

• We show that in a realistic model these constraints are relaxed, making $N_1$ leptogenesis viable.
• To illustrate this, we calculate the baryon asymmetry of the Universe $ Y_B $ from flavoured $ N_1 $ leptogenesis in a recently proposed $ \Delta(27) \times SO(10) $ SUSY GUT.
• The flavoured Boltzmann equations are solved numerically, and comparison with the observed $ Y_B $ places constraints on the allowed values of right-handed neutrino masses and neutrino Yukawa couplings.