Galaxy cluster angular-size data constraints on dark energy

We use angular size versus redshift data for galaxy clusters provided by Bonamente and collaborators 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 galaxy cluster angular-size data with the 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.