Observational constraints on a Yang-Mills condensate dark energy model

Using the recently released Union2 compilation with 557 Type Ia supernovae, the shift parameter of the cosmic microwave background given by the WMAP7 observations and the baryon acoustic oscillation measurement from the Sloan Digital Sky Survey, we perform the χ2 analysis on the 1-loop Yang-Mills condensate (YMC) dark energy model. The analysis has been made for both non-coupling and coupling models with Ωm0 and w0 being treated as free parameters. It is found that χ2min = 542.870 at Ωm0 0.2701 and w0 = -0.9945 for the non-coupling model, and χ2min 542.790 at γ = -0.015, Ωm0 0.2715 and w0 = -0.9969 for the coupling model. Comparing with the ΛCDM model, the YMC model has a smaller χ2min, but it has greater values of the Bayesian and Akaike information criteria. Overall, YMC is as robust as ΛCDM. (paper)