HEP Colloquia 2026

by Dr Nicola Cargioli (Istituto Nazionale di Fisica Nucleare-Sezione di Cagliari)

Wednesday 18 Feb 2026, 14:30 → 15:30 Europe/Rome

Sala Consiliare (Department of Physics)

Tackling the Standard Model from the Neutrino perspective

The Standard Model of particle physics provides an exceptionally successful description of fundamental interactions, yet it continues to be tested with increasing precision across a wide range of experimental settings. Among all known particles, neutrinos play a particularly special role: they are electrically neutral, extremely weakly interacting, and offer sensitive probes of electroweak dynamics in regimes that are complementary to high-energy collider experiments.
In this seminar, I will present the results of a comprehensive global analysis of elastic neutrino–electron and coherent neutrino–nucleus scattering data, combining accelerator, reactor, and solar measurements within a unified theoretical framework. This approach enables neutrino interactions to serve as an independent precision test of electroweak physics based solely on neutrino observables.
We identify two key precision observables: the effective neutrino charge radii and the neutrino–electron neutral current couplings, gV and gA. The charge radii are constrained using both neutrino–electron and neutrino–nucleus data, while the neutral current couplings gV and gA are extracted from neutrino–electron scattering alone.
The global fit yields updated and competitive bounds on neutrino charge radii and a precision determination of flavor-independent electroweak couplings, demonstrating that current neutrino data, when consistently combined, already allow for a genuine and competitive test of the Standard Model without relying on non-neutrino inputs.
Interestingly, the analysis reveals two degenerate solutions in the electroweak parameter space: the Standard Model solution and a second, non-standard solution involving a swap of neutral current couplings, which is slightly preferred by the data. I will discuss the origin of this degeneracy, its physical interpretation, and how future neutrino experiments may resolve it, strengthening the role of neutrinos as precision probes of fundamental physics.