My research activities fall primarily under astroparticle physics, both from a theoretical and phenomenological point of view, with particular attention to the physics of neutrino oscillations and to the tests of cosmological models. In this field, many relevant results of great impact in the scientific community have been obtained, especially with respect to the interpretation of the anomaly of atmospheric neutrinos, the deficit of solar neutrinos, the connections with oscillation searches at reactors and accelerators. The global analysis of the phenomenology of neutrino oscillations has been pursued with methodological accuracy and original and innovative ideas leading to widely appreciated results,among which the constraints to the oscillation parameters. Other researches focused on the phenomena of neutrino autointeractions in supernovae, some innovative tests of cosmological models and the use of wavelets in medical physics . I started my research in physics in 1998, studying the atmospheric neutrino anomaly and the results of the Super-Kamiokande experiment. I started and continuously improved the accurate calculation of the atmospheric neutrino event distributions, as well as the statistical analysis necessary to constrain the various theoretical models. Thank to the methodological precision and originality the approach, these studies began a reference for the sector (full three-flavors analysis, inclusion of the second octant of theta_23, effects of the variable profile of terrestrial matter traversed). Moreover, relevant bounds on nonstandard theoretical models, as neutrino decays, decoherence, violations of principles of relativity, and with sterile neutrinos have been obtained. Subsequently, pioneering combined analyses of the phenomenology of atmospheric and accelerator and solar neutrino data were performed, in both standard and nonstandard theoretical scenarios, introducing the pull method that was later adopted by many experimental collaborations. More recently, the potential of the project PINGU, aimed at determining the hierarchy of neutrino mass, has been studied. In particular, the implications of possible systematic shape errors of the event spectrum on the sensitivity to the hierarchy
have been analysed, as well as correlations between the determination of the hierarchy and the octant of theta_ 23. The possible determination of the hierarchy through experiments with neutrinos from medium-baseline reactors has also been studied. For the first time in literature, the impact on the sensitivity to hierarchy and on the accuracy of the measurement of the oscillation parameters of the recoil of the neutron in the inverse beta decay, of the effect of multiple reactors, of geo-neutrinos and of the degeneracy between errors on the reconstructed neutrino energy and the shape of the spectrum of neutrinos from the reactor, have been taken into account. Also for the first time correlations between observables depending on the absolute neutrino masses and data form precision cosmology, single and double beta decay have been studied, leading to constraints on the parameters of mass and mixing of neutrinos that have become a standard reference in many theoretical and experimental work, and continue to be mentioned in reviews on neutrinos of the Particle Data Group. Another area of great interest for neutrino physics , in which were obtained important results, is that of the oscillations of the neutrinos from Supernova. The description and understanding of collective oscillations required the development of analytical, semi-analytical and numerical methods of great complexity. Relevant results in the case of oscillations in three generations, in the single and multi angle approximation, have been obtained. With the same accurate methodological approach adopted in neutrino physics, I have carried out tests of standard and nonstandard cosmological models through the analysis of specific distributions of sources. In particular, I have obtained non-trivial constraints on a set of cosmological parameters and on the anisotropy of the universe from the study of the distribution of galaxy clusters and of the redshift distribution ofType IA supernovae, possibly in combination with other data.
Lecturer of General Physics, Classical and Quantum Field Theory, Elementary Particles, Astroparticle Physics.