Uniting Low-Scale Leptogenesis Mechanisms.

In this Letter we demonstrate that what was previously considered as different mechanisms of baryon asymmetry generation involving two right-handed Majorana neutrinos with masses far below the Grand Unified Theory scale---leptogenesis via neutrino oscillations and resonant leptogenesis---are actually united. We show that the observed baryon asymmetry can be generated for all experimentally allowed values of the right-handed neutrino masses above ${M}_{N}\ensuremath{\gtrsim}100\text{ }\text{ }\mathrm{MeV}$. Leptogenesis is effective in a broad range of the parameters, including mass splitting between two right-handed neutrinos as big as $\mathrm{\ensuremath{\Delta}}{M}_{N}/{M}_{N}\ensuremath{\sim}0.1$, as well as mixing angles between the heavy and light neutrinos large enough to be accessible to planned intensity experiments or future colliders.