Cosmological parameters from the first results of boomerang - art. no. 042001

The anisotropy of the cosmic microwave background radiation contains inform ation about the contents and history of the universe. We report new limits on cosmological parameters derived from the angular power spectrum measured in the first Antarctic flight of the Boomerang experiment. Within the fram ework of models with adiabatic perturbations, and using only weakly restric tive prior probabilities on the age of the universe and the nubble expansio n parameter h, we find that the curvature is consistent with Rat and that t he primordial fluctuation spectrum is consistent with scale invariant, in a greement with the basic inflation paradigm. We find that the data prefer a baryon density Omega (b)h(2) above, though similar to, the estimates from l ight element abundances and big bang nucleosynthesis. When combined with la rge scale structure observations, the Boomerang data provide clear detectio ns of both dark matter and dark energy contributions to the total energy de nsity Omega (tot), independent of data from high-redshift supernovae.