More Axions from Strings
High Energy Physics - Phenomenology
2021-03-23 v2 Cosmology and Nongalactic Astrophysics
High Energy Physics - Theory
Abstract
We study the contribution to the QCD axion dark matter abundance that is produced by string defects during the so-called scaling regime. Clear evidence of scaling violations is found, the most conservative extrapolation of which strongly suggests a large number of axions from strings. In this regime, nonlinearities at around the QCD scale are shown to play an important role in determining the final abundance. The overall result is a lower bound on the QCD axion mass in the post-inflationary scenario that is substantially stronger than the naive one from misalignment.
Keywords
Cite
@article{arxiv.2007.04990,
title = {More Axions from Strings},
author = {Marco Gorghetto and Edward Hardy and Giovanni Villadoro},
journal= {arXiv preprint arXiv:2007.04990},
year = {2021}
}
Comments
19 pages + appendices