A search for chameleon particles using a photon regeneration technique
  We report the first results from the GammeV search for chameleon particles, which may be created via photon-photon interactions within a strong magnetic field. Chameleons are hypothesized scalar fields that could explain the dark energy problem. We implement a novel technique to create and trap the reflective particles within a jar and to detect them later via their afterglow as they slowly convert back into photons. These measurements provide the first experimental constraints on the couplings of chameleons to photons. 
A. S. Chou (1), W. Wester (2), A. Baumbaugh (2), H. R. Gustafson (3),   Y. Irizarry-Valle (2), P. O. Mazur (2), J. H. Steffe...