Perturbativity in the seesaw mechanism

Abstract

We consider the Standard Model extended by right-handed neutrinos to explain massive neutrinos through the seesaw mechanism. The new fermion can be observed when it has a sufficiently small mass and large mixings to left-handed neutrinos. If such a particle is the lightest right-handed neutrino, its contribution to the mass matrix of active neutrinos needs to be canceled by that of a heavier one. Yukawa couplings of the heavier one are then larger than those of the lightest one. We show that the perturbativity condition gives a severe upper bound on the mixing of the lightest right-handed neutrino, depending on the masses of heavier ones. Models of high energy phenomena, such as leptogenesis, can be constrained by low energy experiments.

v3: 7 pages, published version, v2: 6 pages, references added, v1: 5 pages, 3 figures

References in corpus (10)

• Big-Bang Nucleosynthesis
• A facility to Search for Hidden Particles at the CERN SPS: the SHiP physics case
• Neutrinos and Collider Physics
• Prospects of Heavy Neutrino Searches at Future Lepton Colliders
• Sterile neutrinos: direct mixing effects versus induced mass matrix of active neutrinos
• On the importance of the 1-loop finite corrections to seesaw neutrino masses
• Heavy Neutrinos and the Kinematics of Tau Decays
• Search for Heavy Right Handed Neutrinos at the FCC-ee
• Seesaw mechanism at electron-electron colliders
• Fair scans of the seesaw. Consequences for predictions on LFV processes

Cited by in corpus (5)

• Probing Leptogenesis
• Probing Leptogenesis at Future Colliders
• A frequentist analysis of three right-handed neutrinos with GAMBIT
• Perspectives for tests of neutrino mass generation at the GeV scale: Experimental reach versus theoretical predictions
• What if a specific neutrinoless double beta decay is absent