Galaxy cluster angular size data constraints on dark energy
  We use angular size versus redshift data for galaxy clusters from Bonamente
et al. (2006) to place constraints on model parameters of constant and
time-evolving dark energy cosmological models. These constraints are compatible
with those from other recent data, but are not very restrictive. A joint
analysis of the angular size data with more restrictive baryon acoustic
oscillation peak length scale and supernova Type Ia apparent magnitude data
favors a spatially-flat cosmological model currently dominated by a
time-independent cosmological constant but does not exclude time-varying dark
energy.
