Extended Mosaic Observations with the Cosmic Background Imager
/ Authors
A. Readhead, B. Mason, C. Contaldi, T. Pearson, J. R. Bond, Steven T. Myers, S. Padin, S. Padin, J. Sievers, J. Sievers
and 15 more authors
J. Cartwright, J. Cartwright, M. Shepherd, D. Pogosyan, D. Pogosyan, S. Prunet, P. Altamirano, R. Bustos, L. Bronfman, S. Casassus, W. Holzapfel, J. May, U. Pen, Sergio N. Torres, P. Udomprasert
/ Abstract
Two years of microwave background observations with the Cosmic Background Imager (CBI) have been combined to give a sensitive, high-resolution angular power spectrum over the range 400 < l < 3500. This power spectrum has been referenced to a more accurate overall calibration derived from the Wilkinson Microwave Anisotropy Probe (WMAP). The data cover 90 deg 2, including three pointings targeted for deep observations. The uncertainty on the l > 2000 power previously seen with the CBI is reduced. Under the assumption that any signal in excess of the primary anisotropy is due to a secondary Sunyaev-Zeldovich anisotropy in distant galaxy clusters, we use CBI, Arcminute Cosmology Bolometer Array Receiver, and Berkeley-Illinois-Maryland Association array data to place a constraint on the present-day rms mass fluctuation on 8 h-1 Mpc scales, σ8. We present the results of a cosmological parameter analysis on the l < 2000 primary anisotropy data that show significant improvements in the parameters as compared to WMAP alone, and we explore the role of the small-scale cosmic microwave background data in breaking parameter degeneracies.
Journal: The Astrophysical Journal
DOI: 10.1086/421105