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 chi(2) 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 Omega(m0) and w(0) being treated as free parameters. It is found that chi(2)(min) = 542.870 at Omega(m0) = 0.2701 and w(0) = -0.9945 for the non-coupling model, and chi(2)(min) = 542.790 at gamma = -0.015, Omega(m0) = 0.2715 and w(0) = -0.9969 for the coupling model. Comparing with the Lambda CDM model, the YMC model has a smaller chi(2)(min), but it has greater values of the Bayesian and Akaike information criteria. Overall, YMC is as robust as Lambda CDM.