  We present the most recent results of both aspects of the GammeV experiment.
The first aspect is a search for axion-like particles using a variable
baseline, "light-shining-through-a-wall" technique. This search excludes the
particle interpretation of the PVLAS signal with high confidence. The second
aspect of the GammeV experiment is a search for chameleon particles, scalar
particles which may be responsible for the dark energy of the universe. This is
accomplished by looking for a characteristic afterglow signature from a
"particle-in-a-jar" experiment whereby chameleon particles become trapped in a
region with a high magnetic field and slowly decay into detectable photons.
This is the first use of this experimental technique to probe for these
particles. We place interesting limits on a limited range of general chameleon
models. These limits are complimentary to other experiments, such as torsion
pendulum experiments, which probe for forces that would result from new scalar
particles.
