Beam mismatch effects in Cosmic Microwave Background polarization measurements

C. Rosset (1) , V. Yurchenko (2) , J. Delabrouille (3) , J. Kaplan (1) , Y. Giraud-Héraud (1) , J.-M. Lamarre (4) , A. J. Murphy (2)

1 APC - Cosmologie
2 Experimental Physics Department
3 APC-Gravitation - APC - Gravitation
4 LERMA - Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique

Measurement of cosmic microwave background polarization is today a major goal of observational cosmology. The level of the signal to measure, however, makes it very sensitive to various systematic effects. In the case of Planck, which measures polarization by combining data from various detectors, the beam asymmetry can induce a temperature leakage or a polarization mode mixing. In this paper, we investigate this effect using realistic simulated beams and propose a first-order method to correct the polarization power spectra for the induced systematic effect.

Mots clés: cosmology; cosmic microwave background; polarization

Domaines: Cosmologie et astrophysique extra-galactique [astro-ph.CO]; Cosmologie et astrophysique extra-galactique [astro-ph.CO]; Astrophysique [astro-ph]

C. Rosset, V. Yurchenko, J. Delabrouille, J. Kaplan, Y. Giraud-Héraud, et al.. Beam mismatch effects in Cosmic Microwave Background polarization measurements. Astronomy and Astrophysics - A&A, 2007, 464, pp.405-415. ⟨10.1051/0004-6361:20042230⟩. ⟨hal-00003136v2⟩