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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Constraining unparticle physics with cosmology and astrophysics.
1Department of Physics, Brookhaven National Laboratory, Upton, NY 11973, USA. hooman@bnl.gov
Physical Review Letters
|October 13, 2007
Summary
Cosmology and astrophysics can constrain "unparticle" physics, which interacts weakly with the Standard Model (SM). This research explores how these cosmic observations can bound unparticle-SM interactions and their potential relic density.
Area of Science:
- Theoretical Physics
- Cosmology
- Astrophysics
Background:
- A scale-invariant
- unparticle
- sector with a nontrivial infrared fixed point may couple to the Standard Model (SM) via higher-dimensional operators.
- These interactions are weak at low energies, obscuring unparticle phenomena.
Purpose of the Study:
- To demonstrate how cosmology and astrophysics can provide significant bounds on the strength of unparticle-SM interactions.
- To discuss the possibility of a non-negligible unparticle relic density today.
Main Methods:
- Utilizing cosmological and astrophysical observations.
- Analyzing the constraints imposed by these observations on theoretical models.
Main Results:
- Cosmology and astrophysics can place significant bounds on unparticle-SM interaction strengths.
- The potential for a non-negligible unparticle relic density is discussed.
Conclusions:
- Cosmic observations offer a powerful tool to probe hidden sectors like unparticles.
- Further investigation into unparticle relic density is warranted.
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