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Updated: Jun 8, 2026
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Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
Search for chameleon scalar fields with the axion dark matter experiment
G Rybka1, M Hotz, L J Rosenberg
1University of Washington, Seattle, Washington 98195, USA.
Physical Review Letters
|September 28, 2010
Summary
This study searched for chameleon particles, potential dark energy candidates, using the ADMX experiment. New limits were set on the coupling between chameleons and photons, advancing beyond the standard model physics searches.
Area of Science:
- Particle physics
- Cosmology
- Astroparticle physics
Background:
- Scalar fields with chameleon properties are candidates for dark energy.
- These fields may interact with photons, leading to detectable effects.
- Theories beyond the standard model often include such scalar fields.
Purpose of the Study:
- To conduct the first search for chameleon particles using a microwave cavity.
- To set new limits on the coupling strength between scalar chameleons and photons.
- To probe a specific range of effective chameleon masses.
Main Methods:
- Utilized the ADMX (Axion Dark Matter eXperiment) microwave cavity.
- Searched for the afterglow signal from photon-chameleon-photon transitions.
- Set limits on the scalar chameleon-photon coupling parameter (βγ).
Main Results:
- Established a new experimental limit on scalar chameleon-photon coupling.
- Excluded coupling values (βγ) between 2×10^9 and 5×10^14.
- Constrained chameleon properties for effective masses in the 1.9510–1.9525 μeV range.
Conclusions:
- The ADMX experiment provides the first cavity-based constraints on scalar chameleon properties.
- The results exclude a significant parameter space for chameleon dark energy models.
- This work opens avenues for future searches of chameleon particles and beyond standard model physics.
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