The Kolmogorov-Smirnov test for the CMB

TL;DR

This paper applies the Kolmogorov-Smirnov test to the cosmic microwave background data, confirming Gaussianity and setting bounds on residual point source contamination, demonstrating the test's potential for future cosmological analyses.

Contribution

It demonstrates that, with proper de-correlation, the Kolmogorov-Smirnov test is compatible with Gaussian CMB fluctuations and establishes its utility in constraining residual point sources.

Findings

CMB data are compatible with Gaussian fluctuations.

The Kolmogorov-Smirnov test can set upper bounds on residual point source power.

The method shows promise for analyzing future datasets like Planck.

Abstract

We investigate the statistics of the cosmic microwave background using the Kolmogorov-Smirnov test. We show that, when we correctly de-correlate the data, the partition function of the Kolmogorov stochasticity parameter is compatible with the Kolmogorov distribution and, contrary to previous claims, the CMB data are compatible with Gaussian fluctuations with the correlation function given by standard Lambda-CDM. We then use the Kolmogorov-Smirnov test to derive upper bounds on residual point source power in the CMB, and indicate the promise of this statistics for further datasets, especially Planck, to search for deviations from Gaussianity and for detecting point sources and Galactic foregrounds.