Comments on Axions, Domain Walls, and Cosmic Strings

Abstract

Axions have for some time been considered a plausible candidate for dark matter. They can be produced through misalignment, but it has been argued that when inflation occurs before a Peccei-Quinn transition, appreciable production can result from cosmic strings. This has been the subject of extensive simulations. But there are reasons to be skeptical about the possible role of axion strings. We review and elaborate on these questions, and argue that parametrically strings are already accounted for by the assumption of random misalignment angles. We review and elaborate on these questions, and provide several qualitative arguments that parametrically strings are already accounted for by the assumption of random misalignment angles. The arguments are base on considerations of the collective modes of the string solutions, on computations of axion radiation in particular models, and reviews of simulations.

31 pages, 3 figures; published version

References in corpus (6)

• Dark Matter from Axion Strings with Adaptive Mesh Refinement
• The dark-matter axion mass
• Improved estimation of radiated axions from cosmological axionic strings
• Decay of Cosmic String Loops Due to Particle Radiation
• Approach to scaling in axion string networks
• Comment on "More Axions from Strings''

Cited by in corpus (7)

• Dark Matter from Axion Strings with Adaptive Mesh Refinement
• The Cosmic Axion Background
• The Irreducible Axion Background
• Extraterrestrial Axion Search with the Breakthrough Listen Galactic Center Survey
• QCD Axion Kinetic Misalignment without Prejudice
• An introduction to axions and their detection
• Low Energy Effective Theory for Axion Strings