Low-scale leptogenesis with low-energy Dirac CP-violation

We study the freeze-in scenario of leptogenesis via oscillations within the type-I seesaw model with two quasidegenerate heavy Majorana neutrinos N-1,N-2 having masses M-2 > M-1 similar to (0.1-100) GeV, (M-2-M-1)/M-1 << 1, focusing on the role of the CP-violation provided by the Dirac phase delta of the Pontecorvo-Maki-Nakagawa-Sakata lepton mixing matrix. We find that viable leptogenesis can be due solely to CP-violating values of delta and that the N-1,N-2 total mixing squared Theta(2) = Sigma(alpha)Theta(2)(alpha) needed is within the reach of future experiments, Theta(alpha) parametrizing the coupling to the charged lepton alpha=e, mu, tau. Furthermore, the required parameter space differs from that associated with additional Casas-Ibarra sources of CP-violation. Future determination of delta, Theta(2) and/or the ratios Theta(2)(tau)Theta(2)(mu)Theta(2)(e) would provide a critical test of the considered scenario.