Reconstruction of high-resolution Sunyaev-Zeldovich maps from heterogeneous data sets using needlets

Abstract

The aim of this work is to propose a joint exploitation of heterogeneous data sets from high-resolution/few-channel experiments and low-resolution/many-channel experiments by using a multi-scale needlet Internal Linear Combination (ILC) in order to optimize the thermal Sunyaev-Zeldovich (SZ) effect reconstruction at high resolution. We highlight that needlet ILC is a powerful and tunable component separation method that can easily deal with multiple experiments with various specifications. Such a multi-scale analysis renders possible the joint exploitation of high-resolution and low-resolution data by performing for each needlet scale a combination of some specific channels, either from one data set or from both data sets, selected for their relevance to the angular scale considered, thus allowing us to simultaneously extract high-resolution SZ signal from compact clusters and remove Galactic foreground contamination at large scales. © 2013 The Authors. Published by Oxford University Press on behalf of the Royal Astronomical Society.