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arXiv · 1902.00569

Bandpass mismatch error for satellite CMB experiments II: Correcting for the spurious signal

Ranajoy Banerji·Guillaume Patanchon·Jacques Delabrouille·Masashi Hazumi·Duc Thuong Hoang·Hirokazu Ishino·Tomotake Matsumura
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Abstract

Future Cosmic Microwave Background (CMB) satellite missions aim at using the B-mode polarisation signal to measure the tensor-to-scalar ratio $r$ with a sensitivity $\sigma(r)$ of the order of $\leq 10^{-3}$. Small uncertainties in the characterisation of instrument properties such as the spectral filters can lead to a leakage of the intensity signal to polarisation and can possibly bias any measurement of a primordial signal. In this paper we discuss methods for avoiding and correcting for the intensity to polarisation leakage due to bandpass mismatch among detector sets. We develop a template fitting map-maker to obtain an unbiased estimate of the leakage signal and subtract it out of the total signal. Using simulations we show how such a method can reduce the bias on the observed B-mode signal by up to $3$ orders of magnitude in power.

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Ranajoy Banerji, Guillaume Patanchon, Jacques Delabrouille, Masashi Hazumi, Duc Thuong Hoang, Hirokazu Ishino, Tomotake Matsumura. 2019-02-01. Bandpass mismatch error for satellite CMB experiments II: Correcting for the spurious signal. https://doi.org/10.1088/1475-7516%2F2019%2F07%2F043

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