Estimating g_NL for Planck
Galliano, Dominic (Institute of Cosmology and Gravitation - University of Portsmouth)

With Planck's more precise measurements of the CMB Anisotropies at small scales, new independent measures of non-Gaussianity are being developed which are based on 4 point correlation functions, such as g_NL. So far, g_NL estimators have been derived for the local form, the equilateral form and isocurvature modes. However measuring g_NL brings new challenges in data processing. An extra correlation point gives more degrees of freedom, which together with Planck's precision at small scales means a lot more data needs reducing. How will this affect the variance on g_NL estimators? In this talk I will go through problems with estimating the variance of these estimators for Planck, and talking about how high performance computing is helping us solve this. I will also give the estimates for the variance of different g_NL estimators we can expect when using them on Planck data.