Theoretical neutrino physics revolves around using experimental data and theoretical insights to advance our understanding of how neutrinos interact and oscillate, what determines the fundamental parameters that control their behaviour, how they can help us explore extensions of the Standard Model of particle physics, and what they can teach us about extreme astrophysical environments like supernovae and the early Universe. At CERN, our main research interests in theoretical neutrino physics are:
The periodic conversion of one neutrino flavour into another in flight is perhaps the most intriguing property of neutrino. The quantum mechanics underlying this process are by now well understood, so current theoretical research focuses on helping experiments exploit the incoming data in the optimal way. This goes hand in hand with experimental progress.
Accelerator-based neutrino experiments rely on neutrino–nucleus interactions to detect neutrinos. But calculating the cross sections for such processes is a formidable task. Depending on the beam energy, the neutrino either interacts with whole nucleons (quasi-elastic scattering), or it excites these nucleons (resonance production), or it resolves their substructure and interacts with individual quarks (deep-inelastic scattering). Moreover, nucleons are bound in nuclei, which adds uncertainties in their initial state wave function and in the behaviour of the interaction products as they leave the nucleus.
Neutrino oscillation experiments offer unique possibilities to probe extensions of the Standard Model. For instance, we study the manifold ways in which these experiments can help unravel the mystery of dark matter.
The Universe is full of neutrino sources – stars, supernovae, neutron stars, active galactic nuclei, and even the Big Bang itself. Studying these neutrinos can teach us a great deal about fascinating astrophysical processes. As theoretical physicists, we relate astronomical observations to the properties and the evolution of the sources. Like all research in theoretical physics, addressing these topics is a truly international effort that relies on collaboration and discussion with experts worldwide, so CERN’s extensive visitor programs are essential for success.
