Exotic axion cosmology in theories with phase transitions below the QCD scale.
We show that axion phenomenology may be significantly different than conventionally assumed in theories which exhibit late phase transitions (below the QCD scale). In such theories, one can find multiple pseudoscalars with axionlike couplings to matter, including a string scale axion, whose decay constant far exceeds the conventional cosmological bound. Such theories have several dark matter candidates.
Institute for Nuclear Theory, University of Washington, Seattle, Washington 98195, USA. dbkaplan@phys.washington.edu
David B
DB
Kaplan
Kathryn M
KM
Zurek