ARGO Cosmic Microwave Background Anisotropy Measurement Constraints on Open and Flat‐Λ Cold Dark Matter Cosmogonies

Abstract

We use data from the ARGO cosmic microwave background (CMB) anisotropy experiment to constrain cosmogonies. We account for the ARGO beamwidth and calibration uncertainties, and we marginalize over the offset removed from the data. Our derived amplitudes of the CMB anisotropy detected by the ARGO experiment are smaller than those derived previously. We consider open and spatially flat-Λ cold dark matter cosmogonies, with the clustered-mass density parameter Ω0 in the range 0.1-1, the baryonic-mass density parameter ΩB in the range 0.005-0.029 h−2, and the age of the universe t0 in the range 10-20 Gyr. Marginalizing over all parameters but Ω0, the ARGO data favor an open (spatially flat-Λ) model with Ω0=0.23 (0.1). However, these numerical values are model dependent. At the 2 σ confidence level, model normalizations deduced from the ARGO data are consistent with those drawn from the UCSB South Pole 1994, MAX 4+5, White Dish, and SuZIE data sets. The ARGO open-model normalizations are also consistent with those deduced from the Differential Microwave Radiometer (DMR) data. However, for most spatially flat-Λ models, the DMR normalizations are more than 2 σ above the ARGO ones.