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arXiv · 1910.11327

The effects of varying depth in cosmic shear surveys

Sven Heydenreich·Peter Schneider·Hendrik Hildebrandt·Marika Asgari·Catherine Heymans·Benjamin Joachimi·Konrad Kuijken·Chieh-An Lin·Tilman Tröster·Jan Luca van den Busch
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Abstract

We present a semi-analytic model for the shear two-point correlation function of a cosmic shear survey with non-uniform depth. Ground-based surveys are subject to depth variations that primarily arise through varying atmospheric conditions. For a survey like the Kilo-Degree Survey (KiDS), we find that the measured depth variation increases the amplitude of the observed shear correlation function at the level of a few percent out to degree-scales, relative to the assumed uniform-depth case. The impact on the inferred cosmological parameters is shown to be insignificant for a KiDS-like survey. For next-generation cosmic shear experiments, however, we conclude that variable depth should be accounted for.

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Sven Heydenreich, Peter Schneider, Hendrik Hildebrandt, Marika Asgari, Catherine Heymans, Benjamin Joachimi, Konrad Kuijken, Chieh-An Lin, Tilman Tröster, Jan Luca van den Busch. 2019-12-16. The effects of varying depth in cosmic shear surveys. https://doi.org/10.1051/0004-6361%2F201936966

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