TY  - JOUR
AU  - Donini, A.
AU  - Hernandez, P.
AU  - Lopez-Pavon, J.
AU  - Maltoni, M.
AU  - Schwetz, T.
PY  - 2012
DA  - 2012//
TI  - The minimal 3+2 neutrino model versus oscillation anomalies
T2  - J. High Energy Phys.
JO  - Journal of High Energy Physics
SP  - 161
EP  - 20pp
VL  - 07
IS  - 7
PB  - Springer
KW  - Neutrino Physics
KW  - Beyond Standard Model
AB  - We study the constraints imposed by neutrino oscillation experiments on the minimal extension of the Standard Model that can explain neutrino masses, which requires the addition of just two singlet Weyl fermions. The most general renormalizable couplings of this model imply generically four massive neutrino mass eigenstates while one remains massless: it is therefore a minimal 3+2 model. The possibility to account for the confirmed solar, atmospheric and long-baseline oscillations, together with the LSND/MiniBooNE and reactor anomalies is addressed. We find that the minimal model can fit oscillation data including the anomalies better than the standard 3 nu model and similarly to the 3 + 2 phenomenological models, even though the number of free parameters is much smaller than in the latter. Accounting for the anomalies in the minimal model favours a normal hierarchy of the light states and requires a large reactor angle, in agreement with recent measurements. Our analysis of the model employs a new parametrization of seesaw models that extends the Casas-Ibarra one to regimes where higher order corrections in the light-heavy mixings are significant.
SN  - 1126-6708
UR  - http://arxiv.org/abs/1205.5230
UR  - https://doi.org/10.1007/JHEP07(2012)161
DO  - 10.1007/JHEP07(2012)161
LA  - English
N1  - WOS:000307299800039
ID  - Donini_etal2012
ER  -