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arXiv · 2510.26767

Unbiased Primordial Gravitational Wave Inference from the CMB with SMICA

Alexander Steier·Shamik Ghosh·Jacques Delabrouille
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Abstract

The detection of primordial gravitational waves in Cosmic Microwave Background B-mode polarization observations requires accurate and robust subtraction of astrophysical contamination. We show, using a blind Spectral Matching Independent Component Analysis, that it is possible to infer unbiased estimates of the primordial B-mode signal from ground-based observations of a small patch of sky even for highly complex foreground contamination. This work, originally performed in the context of configuration studies for a future CMB-S4 observatory, is highly relevant for the analysis of observations by the current generation of CMB experiments.

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Alexander Steier, Shamik Ghosh, Jacques Delabrouille. 2025-10-30. Unbiased Primordial Gravitational Wave Inference from the CMB with SMICA. https://doi.org/10.1088/1475-7516%2F2026%2F02%2F080

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