Phenomenological implications of neutrino effective theories

There are few but strong indications that the Standard Model of Particle Physics cannot be the ultimate theory of nature. The increasing number of proposed extensions, together with the lack of new particles found by the LHC, is prompting us to consider the effective field theories (EFT) as the best framework to explore deviations from the Standard Model. Nevertheless, the most commonly explored EFT framework does not consider the existence of new light particles, such as those predicted by many theories trying to explain the origin of neutrino masses or dark matter, and therefore cannot account for two of the biggest unsolved problems in particle physics.Considering the existence of new sterile neutrinos for definiteness, this project aims at building a new EFT framework where additional light particles are included to the commonly used EFT formalism. First, it will extend the few available works in the subject to construct a theoretically consistent framework. In the second part, it will make use of this formalism to identify and compute the most relevant predictions for the near-future experimental landscape.