A Simple Test for Non-Gaussianity in Cosmic Microwave Background Radiation Measurements

Abstract

view Abstract Citations (4) References (16) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS A Simple Test for Non-Gaussianity in Cosmic Microwave Background Radiation Measurements Graham, Paul ; Turok, Neil ; Lubin, P. M. ; Schuster, J. A. Abstract We propose a set of statistics for detecting non-Gaussianity in one-dimensional cosmic microwave background radiation (CMBR) anisotropy data sets. These statistics are both simple and, according to calculations over a space of linear combinations of three-point functions, nearly optimal at detecting certain types of nonGaussian features. We use this statistic to analyze the anisotropy detected by the UCSB SP91 experiment. According to this statistic the mean of the four frequency channels is significantly non-Gaussian. If this signal represents primordial CMBR fluctuations, it would be highly unlikely in a Gaussian theory with a small coherence angle, such as "standard" (n = 1,Ωb = 0.05, h = 0.5, Δ = 0) inflation. We cannot tell whether the observed non-Gaussian signal is cosmological in origin, but if we assume it due instead to foreground emission, and remove the points responsible for the non-Gaussian behavior, the rms of the remaining fluctuations is improbably low for the "standard" inflation theory. Further data are clearly needed before any definitive conclusions may be drawn. We also generalize the ideas behind this statistic to non-Gaussian features that might be detected in other experimental schemes. Publication: The Astrophysical Journal Pub Date: August 1995 DOI: 10.1086/176065 Bibcode: 1995ApJ...449..404G Keywords: COSMOLOGY: COSMIC MICROWAVE BACKGROUND; COSMOLOGY: THEORY; METHODS: STATISTICAL full text sources ADS |