Testing SO(10)-inspired leptogenesis with low energy neutrino experiments

Abstract

We extend the results of a previous analysis of ours showing that, when both heavy and light flavour effects are taken into account, successful minimal (type I + thermal) leptogenesis with SO(10)-inspired relations is possible. Barring fine tuned choices of the parameters, these relations enforce a hierarchical RH neutrino mass spectrum that results into a final asymmetry dominantly produced by the next-to-lightest RH neutrino decays (N_2 dominated leptogenesis). We present the constraints on the whole set of low energy neutrino parameters. Allowing a small misalignment between the Dirac basis and the charged lepton basis as in the quark sector, the allowed regions enlarge and the lower bound on the reheating temperature gets relaxed to values as low as ~ 10^10 GeV. It is confirmed that for normal ordering (NO) there are two allowed ranges of values for the lightest neutrino mass: m_1 \simeq (1-5)\times 10^-3 eV and m_1\simeq (0.03-0.1) eV. For m_1\lesssim 0.01 eV the allowed region in the plane theta_13-theta_23 is approximately bounded by 44 + 3(theta_13-9) \lesssim theta_23 \lesssim 48 + 0.4 (theta_13-5), while the neutrinoless double beta decay effective neutrino mass falls in the range m_ee=(1-3)10^-3 eV for theta_13=(6 -11.5). For m_1 \gtrsim 0.01 eV, one has quite sharply m_ee\simeq m_1 and an upper bound theta_23 \lesssim 46 . These constraints will be tested by low energy neutrino experiments during next years. We also find that inverted ordering (IO), though quite strongly constrained, is not completely ruled out. In particular, we find approximately theta_23 \simeq 43 +12 log(0.2 eV/m_1), that will be fully tested by future experiments.