Bayesian ICA-based source separation of Cosmic Microwave Background by a discrete functional approximation

Simon P. Wilson; Jiwon Yoon

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arXiv · 1011.4018

Bayesian ICA-based source separation of Cosmic Microwave Background by a discrete functional approximation

Simon P. Wilson·Jiwon Yoon

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Abstract

A functional approximation to implement Bayesian source separation analysis is introduced and applied to separation of the Cosmic Microwave Background (CMB) using WMAP data. The approximation allows for tractable full-sky map reconstructions at the scale of both WMAP and Planck data and models the spatial smoothness of sources through a Gaussian Markov random field prior. It is orders of magnitude faster than the usual MCMC approaches. The performance and limitations of the approximation are also discussed.

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Simon P. Wilson, Jiwon Yoon. 2010-11-17. Bayesian ICA-based source separation of Cosmic Microwave Background by a discrete functional approximation. https://arxiv.org/abs/1011.4018

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