Cosmological Results from Five Years of 30 GHz CMB Intensity Measurements with the Cosmic Background Imager

Abstract

We present final results on the angular power spectrum of total intensity anisotropies in the CMB from the CBI. Our analysis includes all primordial anisotropy data collected between January 2000 and April 2005, and benefits significantly from an improved maximum likelihood analysis pipeline. It also includes results from a 30 GHz foreground survey conducted with the Green Bank Telescope (GBT) which places significant constraints on the possible contamination due to foreground point sources. We improve on previous CBI results by about a factor of two in the damping tail. These data confirm, at ~3-sigma, the existence of an excess of power over intrinsic CMB anisotropy on small angular scales (l > 1800). Using the GBT survey, we find currently known radio source populations are not capable of generating the power; a new population of faint sources with steeply rising spectral indices would be required to explain the excess with sources... We also present a full cosmological parameter analysis of the new CBI power spectrum... With CBI alone, the full parameter analysis finds the excess is 1.6-sigma above the level expected for a sigma_8=0.8 universe. We find the addition of high-l CMB data substantially improves constraints on cosmic string contributions to the TT power spectrum as well as the running of the scalar spectral index... We also present forecasts for what other experiments should see at different frequencies and angular resolutions given the excess power observed by CBI. We find that the reported high-l bandpowers from current high resolution CMB bolometer experiments are consistent with each other and CBI if the excess power is due to the SZE at the CBI-level of 2.5 +/- 1 times the sigma_8=0.8 standard SZ template. <Abridged>

arXiv comment38 Pages, 9 Figures, 5 Tables v2 - fixed typos

Cited by in corpus (23)

• Primordial magnetogenesis
• The Atacama Cosmology Telescope: Cosmological parameters from three seasons of data
• The Atacama Cosmology Telescope: Temperature and Gravitational Lensing Power Spectrum Measurements from Three Seasons of Data
• The Atacama Cosmology Telescope: The Receiver and Instrumentation
• Simulations of the Sunyaev-Zel'dovich Power Spectrum with AGN Feedback
• The Atacama Cosmology Telescope: likelihood for small-scale CMB data
• The Atacama Cosmology Telescope: A Measurement of the Cosmic Microwave Background Power Spectrum at 148 and 218 GHz from the 2008 Southern Survey
• The Atacama Cosmology Telescope: A Measurement of the 600< ell <8000 Cosmic Microwave Background Power Spectrum at 148 GHz
• The Atacama Cosmology Telescope: Data Characterization and Map Making
• Reconstruction of the primordial power spectrum of curvature perturbations using multiple data sets
• Mass Function of Rich Galaxy Clusters and Its Constraint on sigma_8
• The Atacama Cosmology Telescope: Calibration with WMAP Using Cross-Correlations
• Measuring our Peculiar Velocity by "Pre-deboosting" the CMB
• Constraints on standard and non-standard early Universe models from CMB B-mode polarization
• Subdegree Sunyaev-Zel'dovich Signal from Multifrequency BOOMERanG observations
• 30 GHz observations of sources in the VSA fields
• Constraining Decaying Dark Matter
• The Cosmic Background Imager 2
• Geometrical measures of non-Gaussianity generated from single field Inflationary models
• An overview of the current status of CMB observations
• Simulations and Observations of the Microwave Universe
• Inflationary study of non-Gaussianity using two-dimensional geometrical measures of CMB temperature maps
• High frequency radio SEDs and polarization fractions of sources in an ACT survey field