Primordial Non-Gaussianity in the Cosmic Microwave Background

Table 1

Hint of local non-Gaussianity at 2𝜎 level.

Data (mask, estimator)	𝑓^localNL±1𝜎 error	Deviation from Gaussianity
WMAP 3-year (Kp0, near-optimal)	87±31	2.8𝜎	Yadav and Wandelt [28]
WMAP 3-year (KQ75, optimal)	58±23	2.5𝜎	Smith et al. [122]
WMAP 3-year (Kp0, near-optimal)	69±30	2.3𝜎	Smith et al. [122]
WMAP 5-year (KQ75, near-optimal)	51±30	1.7𝜎	Komatsu et al. [48]
WMAP 5-year (KQ75, optimal)	38±21	1.8𝜎	Smith et al. [122]

The difference between the results by [28, 122] for WMAP 3-year data using the Kp0 mask can be a result of different choices of weighting in the near-optimal estimator. The optimal estimator has a unique weighting scheme.