How dark is dark energy? A laboratory search for couplings between photons and chameleon dark energy
Dark energy can differ from the cosmological constant, the simplest
model for the cosmic acceleration, either by evolving with time or by
coupling to known particles. Coupled theories typically invoke a
screening mechanism, such as the chameleon mechanism, to explain tight
constraints on fifth forces and the evolution of fundamental constants
locally. I will discuss the GammeV-CHASE experiment, conducted last
year at Fermilab, which was designed to produce, trap, and detect
photon-coupled chameleon dark energy. GammeV-CHASE has improved
constraints on photon-chameleon couplings by orders of magnitude and
has ruled out a range of models at the dark energy scale.
Back to the Astrophysics at Argonne page.