| Etablissement | Université de Batna 1 - Hadj Lakhder | | Affiliation | Département de Physique | | Auteur | LEBBAL, Soumia | | Directeur de thèse | Jamal Mimouni (Professeur) | | Filière | Physique | | Diplôme | Doctorat | | Titre | Probing the Consequences of Extra-neutrinos in Astrophysics | | Mots clés | Sterile Neutrinos, MiniBoone experiment, LSND experiment, neutrino oscillation | | Résumé | In the late 1990s, LSND experiment (an accelerator experiment at Los Alamos National Laboratory) which was based on a muonic antineutrino beam reported the observation of neutrino flavor oscillation on a laboratory length scale (tens of meters). A small oscillation length requires the existence of a more elusive type of neutrino, that could never be detected directly: a low-mass “sterile neutrino” flavor, which does not interact via the weak force.
This claim was confirmed later by the MiniBoone experiment at the Fermilab.
Another hint comes from cosmological observations namely the observation of the CMB anisotropies and LSS distribution which have allowed to probe the radiation density at the CMB decoupling epoch (later time than the nucleosynthesis epoch). The analysis favors existence of extra radiation beyond photons and ordinary neutrinos and supports the existence of low mass sterile neutrinos.
If a fourth flavor of neutrino exists such as a sterile neutrino that cannot be grouped with the three generations of known standard model fermions, then perhaps we can consider whether a 5th neutrino exists, along with an additional lepton and perhaps along with two additional quarks thus resulting in a total of 5 charged leptons and 5 charged antileptons, and 10 quarks and 10 antiquarks. | | Statut | Validé |
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