Generalised CP symmetry in modular-invariant models of flavour

• Main Authors: P.P. Novichkov, J.T. Penedo, S.T. Petcov, A.V. Titov
• Format: Article
• Language: English
• Published: SpringerOpen 2019-07-01
• Series: Journal of High Energy Physics
• Subjects: Beyond Standard Model; CP violation; Neutrino Physics
• Online Access: http://link.springer.com/article/10.1007/JHEP07(2019)165

Abstract The formalism of combined finite modular and generalised CP (gCP) sym-metries for theories of flavour is developed. The corresponding consistency conditions for the two symmetry transformations acting on the modulus τ and on the matter fields are derived. The implications of gCP symmetry in theories of flavour based on modular invariance described by finite modular groups are illustrated with the example of a modular S 4 model of lepton flavour. Due to the addition of the gCP symmetry, viable modular models turn out to be more constrained, with the modulus τ being the only source of CP violation.