Search for Heavy Right Handed Neutrinos at the FCC-ee

Understand

The Standard Model of particle physics is still lacking an understanding of the generation and nature of neutrino masses.

• A favorite theoretical scenario (the see-saw mechanism) is that both Dirac and Majorana mass terms are present, leading to the existence of heavy partners of the light neutrinos, presumably massive and nearly sterile.
• These heavy neutrinos can be searched for at high energy lepton colliders of very high luminosity, such as the Future electron-positron e+e- Circular Collider, FCC-ee (TLEP), presently studied within the Future Circular Collider design study at CERN, as a possible first step.
• A first look at sensitivities, both from neutrino counting and from direct search for heavy neutrino decay, are presented.