Phase Mapping as a Powerful Diagnostic of Primordial Non-Gaussianity

School of Physics & Astronomy, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom(February 2, 2008)The identification and extraction of non-Gaussian signals is one of the main cosmological challengesfacing future experimental measurements of the cosmic microwave background temperature pattern.We present a generalized statistical measure based on a novel technique representation of Fourierphases using the return map. We show that this method is both robust and powerful in comparison,for example, with morphological measures.I. INTRODUCTION