Description:

The fundamental question in neutrino physics.

Yuber Perez, Postdoctoral Researcher

Are neutrinos their own antiparticles? That is, are neutrinos Dirac or Majorana fermions? The basic issue in discriminating between the two types of fermions is that any effect has an helicity suppression factor, a mass to energy ratio. However, the possible detection of the non-relativistic neutrinos created in the early Universe is one promising ways to undertake the Dirac-Majorana question. In this talk we will consider the detection of the cosmic neutrino background, and how the presence of beyond the Standard Model physics can affect it. Also, we will present other possible sources of non-relativistic neutrinos, such as neutrinos emitted from primordial black holes.

Supernovae as laboratories for neutrino physics

Manibrata Sen, Postdoctoral Researcher

During a core-collapse supernova (SN), a large number of neutrinos are emitted, which carry away a major fraction of the binding energy of the star. These neutrinos are our best hopes of probing the dense conditions inside a SN, which are otherwise inaccessible to terrestrial experiments. This, coupled with the fact that the neutrinos automatically traverse a long distance to the Earth, allow us to probe fundamental properties of neutrinos, as well as the progenitor star itself. In this talk, I would like to discuss some of these issues, focussing particularly on two fundamental questions that have baffled the neutrino physics community for ages: (i) Do neutrinos decay? (ii) Are neutrinos Dirac or Majorana? The occurrence of a near galactic SN can help us address these questions!