Current Cosmological Constraints from a 10 Parameter Cosmic Microwave Background Analysis

We compute the constraints on a ``standard'' 10 parameter cold dark matter(CDM) model from the most recent CMB and data and other observations, exploring30 million discrete models and two continuous parameters. Our parameters arethe densities of CDM, baryons, neutrinos, vacuum energy and curvature, thereionization optical depth, and the normalization and tilt for both scalar andtensor fluctuations. Our strongest constraints are on spatial curvature, -0.24 < Omega_k < 0.38,and CDM density, h^2 Omega_cdm <0.3, both at 95%. Including SN 1a constraintsgives a positive cosmological constant at high significance. We explore the robustness of our results to various assumptions. We find thatthree different data subsets give qualitatively consistent constraints. Some ofthe technical issues that have the largest impact are the inclusion ofcalibration errors, closed models, gravity waves, reionization, nucleosynthesisconstraints and 10-dimensional likelihood interpolation.