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arXiv · 2106.04841

The Crab Nebula as a Calibrator for wide-beam Cosmic Microwave Background polarization surveys

Silvia Masi·Paolo de Bernardis·Fabio Columbro·Alessandro Coppolecchia·Giuseppe D'Alessandro·Lorenzo Mele·Alessandro Paiella·Francesco Piacentini
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Abstract

We analyze the effect of polarized diffuse emission in the calibration of wide-beam mm-wave polarimeters, when using the Crab Nebula as a reference source for both polarized brightness and polarization angle. We show that, for CMB polarization experiments aiming at detecting B-mode in a scenario with a tensor to scalar ratio $r \sim 0.001$, wide (a few degrees in diameter), precise ($\sigma_Q$ , $\sigma_U$ $\sim$ 20 $\mu$$K_{CMB}$ arcmin), high angular resolution ($< \mathrm{FWHM}$) reference maps are needed to properly take into account the effects of diffuse polarized emission and avoid significant bias in the calibration.

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Silvia Masi, Paolo de Bernardis, Fabio Columbro, Alessandro Coppolecchia, Giuseppe D'Alessandro, Lorenzo Mele, Alessandro Paiella, Francesco Piacentini. 2021-06-09. The Crab Nebula as a Calibrator for wide-beam Cosmic Microwave Background polarization surveys. https://doi.org/10.3847/1538-4357/ac1860

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