Axion domain wall baryogenesis

Understand

We propose a new scenario of baryogenesis, in which annihilation of axion domain walls generates a sizable baryon asymmetry.

• Successful baryogenesis is possible for a wide range of the axion mass and decay constant, $m \simeq 10^8 -10^{13}$ GeV and $f \simeq 10^{13} - 10^{16}$ GeV.
• Baryonic isocurvature perturbations are significantly suppressed in our model, in contrast to various spontaneous baryogenesis scenarios in the slow-roll regime.
• In particular, the axion domain wall baryogenesis is consistent with high-scale inflation which generates a large tensor-to-scalar ratio within the reach of future CMB B-mode experiments.