Abstract
It has recently been suggested that a scale-invariant “unparticle” sector with a nontrivial infrared fixed point may couple to the standard model (SM) via higher-dimensional operators. The weakness of such interactions hides the unparticle phenomena at low energies. We demonstrate how cosmology and astrophysics can place significant bounds on the strength of unparticle-SM interactions. We also discuss the possibility of a having a non-negligible unparticle relic density today.
- Received 20 June 2007
DOI:https://doi.org/10.1103/PhysRevLett.99.141301
©2007 American Physical Society