Adiabatic versus Isocurvature Non--Gaussianity

Understand

We study the extent to which one can distinguish primordial non--Gaussianity (NG) arising from adiabatic and isocurvature perturbations.

• We make a joint analysis of different NG models based on various inflationary scenarios: local-type and equilateral-type NG from adiabatic perturbations and local-type and quadratic-type NG from isocurvature perturbations together with a foreground contamination by point sources.
• We separate the Fisher information of the bispectrum of CMB temperature and polarization maps by l for the skew spectrum estimator introduced by Munshi & Heavens (2009) to study the scale dependence of the signal-to-noise ratio of different NG components and their correlations.
• We find that the adiabatic and the isocurvature modes are strongly correlated, though the phase difference of acoustic oscillations helps to distinguish them.