IFIC Seminar: Littlest Seesaw Models

by Steve King (University of Southampton)

Tuesday 13 Jun 2023, 12:00 → 13:00 Europe/Madrid

1001-Primera-1-1-1 - Paterna. Seminario (Universe)

After a lengthy introduction to neutrino physics we shall discuss the quest towards a minimal predictive seesaw model able to successfully predict the neutrino masses and mixing parameters with the fewest number of input parameters. We discuss a promising class of such models based on the type I seesaw with two right-handed neutrinos, called constrained sequential dominance (CSD) of level n, where n is a real number, also known as the Littlest Seesaw. For each choice of n, the neutrino mass matrix is determined up to two real parameters plus a phase, leading to a highly predictive scheme. We show how the choice $n=1+\sqrt{6}$ may arise from modular symmetry.