Inationary dilaton-axion magnetogenesis

We discuss the generation of primordial magnetic fields during in ation in dilaton-axion electromagnetism, in which the dilaton and axion dynamics are introduced in terms of two time dependent functions of the cosmic scale factor, I(a)F²/4 and J(a)FF~/4, respectively, where F is the electromagnetic field strength and F~ is its dual. We study the form of J(a) that can generate a large seed magnetic field. Although the J(a) function is model dependent, the axion-photon coupling may open up a new window for a successful in ationary magnetogenesis.