The minimal extension of the SM and the neutrino oscillation data Águila Giménez, Francisco Del Gluza, J. Zrałek, M. Reconciling dark-matter Right-handed neutrinos Scale double-beta Atmospheric neutrinos Sterile neutrino LSND experiment Mass hierarchy Lepton sector CP violation Presented at the XXIII International School of Theoretical Physics "Recent Development in Theory of Fundamental Interactions" Ustrón. Poland, september 15-22, 1999. We study the simplest Standard Model extension with only one extra right-handed neutrino. In this case there are two massless m1,2 and two massive m3,4 neutrinos, and in principle both solar and atmospheric anomalies can be described in two different scenarios, m3 ≪ m4 (scheme I) and m3 ≃ m4 (scheme II). However, neither bi-maximal mixing nor the dark matter problem are explained in this minimal extension. Only scheme II can accommodate simultaneously maximal mixing for atmospheric neutrinos and the small mixing angle MSW solution for the solar anomaly. This scenario can be tested in the BOREXINO experiment. 2014-07-01T08:15:19Z 2014-07-01T08:15:19Z 1999 info:eu-repo/semantics/article Águila, F.; Gluza, J.; Zralek. The minimal extension of the SM and the neutrino oscillation data. Acta Physica Polonica B, 30(11): 3139-3147 (1999). [http://hdl.handle.net/10481/32417] 0587-4254 1509-5770 http://hdl.handle.net/10481/32417 eng http://creativecommons.org/licenses/by-nc-nd/3.0/ info:eu-repo/semantics/openAccess Creative Commons Attribution-NonCommercial-NoDerivs 3.0 License Jagiellonian University