Journal article

Fractional Polarisation of Extragalactic Sources in the 500-square-degree SPTpol Survey

N Gupta, CL Reichardt, PAR Ade, AJ Anderson, M Archipley, JE Austermann, JS Avva, JA Beall, AN Bender, BA Benson, F Bianchini, LE Bleem, JE Carlstrom, CL Chang, HC Chiang, R Citron, C Corbett Moran, TM Crawford, AT Crites, T de Haan Show all

Monthly Notices of the Royal Astronomical Society | Oxford University Press (OUP) | Published : 2019


We study the polarisation properties of extragalactic sources at 95 and 150 GHz in the SPTpol 500 deg2 survey. We estimate the polarised power by stacking maps at known source positions, and correct for noise bias by subtracting the mean polarised power at random positions in the maps. We show that the method is unbiased using a set of simulated maps with similar noise properties to the real SPTpol maps. We find a flux-weighted mean-squared polarisation fraction 〈p2〉 = [8.9 ± 1.1] × 10−4 at 95 GHz and [6.9 ± 1.1] × 10−4 at 150 GHz for the full sample. This is consistent with the values obtained for a sub-sample of active galactic nuclei. For dusty sources, we find 95 per cent upper limits of..

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Awarded by National Science Foundation

Awarded by NSF Physics Frontier Center grant

Awarded by Gordon and Betty Moore Foundation

Awarded by Office of Science of the U.S. Department of Energy

Awarded by Australian Research Council

Funding Acknowledgements

South Pole Telescope (SPT) is supported by the National Science Foundation through grant PLR-1248097. Partial support is also provided by the NSF Physics Frontier Center grant PHY-1125897 to the Kavli Institute of Cosmological Physics at the University of Chicago, the Kavli Foundation, and the Gordon and Betty Moore Foundation grant GBMF 947. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The Melbourne group acknowledges support from the Australian Research Council's Discovery Projects scheme (DP150103208).