Lectures on
Neutrino Mass and Grand Unified Theories

27.07.2009 – 01.08.2009
İstanbul - TURKEY

Lecturer:
Goran Senjanovic (ICTP)

Abstract:

It is often said that neutrino mass is a window to a new physics beyond the standard model (SM). This is certainly true if neutrinos are Majorana particles since the SM with Majorana neutrino mass is not a complete theory. The classical text-book test of neutrino Majorana mass, the neutrino-less double beta decay, depends on the completion, and thus cannot probe neutrino mass. On the other hand, the colliders such as Tevatron or LHC offer a hope of probing directly the origin of neutrino Ma jorana mass through lepton number violating production of like sign lepton pairs. I discuss this at length.

I start my lectures with the in-depth discussion of Majorana and Dirac masses, in both two and four component language. I show how one can use the usual knowledge of the Dirac theory in order to work with Majorana spinors and the appropriate Feynman rules. I discuss next the effective theory of neutrino mass and the usual seesaw mechanisms that lead to it. In order to predict the physical scales and couplings, I turn to grand unification. Both SU(5) and SO(10) theories are covered in some details, including the spinorial representations of orthogonal groups. I then give an example of a predictive SU(5) grand unified theory that results in a hybrid type I and III seesaw with a light fermion triplet below TeV scale, tailor fit for LHC.

Finally, if time permits, I will discuss also some realistic SO(10) models.

Organizers:

Kayhan Ülker (FGE)
Altuğ Özpineci (ODTÜ)