Mapping the Universe with slitless spectroscopy

TL;DR

This paper discusses Euclid's plan to map the universe using slitless spectroscopy, focusing on strategies to mitigate systematic errors in galaxy surveys to improve cosmological measurements.

Contribution

It presents a proposed strategy for mitigating systematic errors in Euclid's slitless spectroscopic survey and propagating uncertainties to cosmological parameters.

Findings

Mitigation strategies for systematic errors are outlined.

Error budget will be dominated by systematics rather than statistical errors.

Approach to propagate mitigation uncertainties to cosmological parameters is discussed.

Abstract

Euclid will survey most of the accessible extragalactic sky with imaging and slitless spectroscopy observations, creating a unique spectroscopic catalog of galaxies with H$\alpha$ line in emission that will map the Universe from $z=0.9$ to $1.8$. With low expected statistical errors, the error budget will likely be dominated by systematic errors related to uncertainties in the data and modelling. I will discuss the strategy that has been proposed to mitigate the expected systematic effects and propagate the uncertainty of mitigation to cosmological parameter errobars.