2015/04/30 by Damian Ejlli
Physics and Astronomy · #Astrophysics and Cosmic Phenomena #Axion #Cosmic microwave background #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Distortion (music) #Field (mathematics) #Magnetic field #Mixing (physics) #Spectral density #Spectral index #astro-ph.CO #gr-qc #hep-ph
paper · pdf · doi:10.1140/epjc/s10052-015-3606-3
published as Eur. Phys. J. C 75 (8) 397 (2015) · Typos corrected. Requested by the referee some additional text has been added. Minor changes. Version to be published at EPJ C
openalex publication_date 2015/08/01 · arxiv created 2015/08/20 · arxiv updated 2015/09/02 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Axion production due to photon–axion mixing in tangled magnetic fields prior to the recombination epoch and magnetic field damping can generate cosmic microwave background (CMB) spectral distortions. In particular, the contribution of both processes to the CMB μ distortion in the case of resonant photon–axion mixing is studied. Assuming that the magnetic field power spectrum is approximated by a power law, PB(k)∝ kn with spectral index n, it is shown that for magnetic field cut-off scales 172.5 pc ≤ λ B≤ 4× 103 pc, the axion contribution to the CMB μ distortion is subdominant in comparison with magnetic field damping in the cosmological plasma. Using the COBE upper limit on μ and for the magnetic field scale λ B≃ 415 pc, a weaker limit in comparison with other studies on the magnetic field strength ( B0≤ 8.5× 10-8 G) up to a factor 10 for the DFSZ axion model and axion mass ma≥ 2.6× 10-6 eV is found. A forecast for the expected sensitivity of PIXIE/PRISM on μ is also presented.