2012/02/29 by Takashi Hiramatsu, Masahiro Kawasaki, Ken'ichi Saikawa +2 · 5 citations
Physics and Astronomy · #Annihilation #Axion #Cold dark matter #Cosmic string #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Dark matter #Domain wall (magnetism) #Lattice (music) #Magnetic field #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum mechanics #String (physics) #Theoretical physics #astro-ph.CO #hep-ph
paper · pdf · doi:10.1103/physrevd.85.105020
published as Phys. Rev. D 85, 105020 (2012); Phys. Rev. D 86, 089902(E) (2012) · 22 pages, 8 figures; a version including corrections to the article published in PRD
openalex publication_date 2012/05/21 · arxiv created 2012/10/16 · arxiv updated 2012/10/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We analyze the spectrum of axions radiated from collapse of domain walls, which have received less attention in the literature. The evolution of topological defects related to the axion models is investigated by performing field-theoretic lattice simulations. We simulate the whole process of evolution of the defects, including the formation of global strings, the formation of domain walls, and the annihilation of the defects due to the tension of walls. The spectrum of radiated axions has a peak at the low frequency, which implies that axions produced by the collapse of domain walls are not highly relativistic. We revisit the relic abundance of cold dark matter axions and find that the contribution from the decay of defects can be comparable with the contribution from strings. This result leads to a more severe upper bound on the axion decay constant.