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 greater than or similar to 100 MeV. Leptogenesis is effective in a broad range of the parameters, including mass splitting between two right-handed neutrinos as big as Delta M-N / M-N similar to 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.