| dc.description |
We study the effect of radiative corrections on the structure of neutrino mass matrix. We analyze the renormalization of the matrix from the electroweak scale m<sub>Z</sub> to the scale m<sub>0</sub> at which the effective operator that gives masses to neutrinos is generated. Apart from Standard Model and MSSM, non-standard extensions of SM are considered at a scale m<sub>X</sub> intermediate between m<sub>Z</sub> and m<sub>0</sub>. We find that the dominant structure of the neutrino mass matrix does not change. SM and MSSM corrections produce small (few percents) independent renormalization of each matrix element. Non-standard (flavor changing) corrections can modify strongly small (sub-dominant) matrix elements, which are important for the low energy phenomenology. In particular, we show that all sub-dominant elements can have purely radiative origin, being zero at m<sub>0</sub>. The set of non-zero elements at m<sub>0</sub> can be formed by (i) diagonal elements (unit matrix); (ii) M<sub>ee</sub> and M<sub>μτ</sub>; (iii)M<sub>ee</sub> and μτ-block elements; (iv) μτ-block elements. In the case of unit matrix, both atmospheric and solar mixing angles and mass squared differences are generated radiatively. |
