Speaker
Description
We study photon-to-axion conversion in stochastic magnetic fields, focusing on the emergence of the nontrivial photon polarizations induced by conversion.
Assuming Gaussian magnetic fields that may possess nonzero helicity, and unpolarized photons as the initial state, we derive expressions for the intensity and linear/circular polarizations of photons after propagation in terms of these spectra.
We find that these statistical quantities depend on the characteristic magnetic field correlation length, the propagation distance, and the axion mass.
Moreover, our analysis reveals that a peak structure appears in the expectation value of the circular polarization in the presence of statistically helical magnetic fields.
We also derive consistency relations among these statistical quantities that hold independently of the specific forms of the magnetic field power spectra.