VIS: the visible imager for Euclid

TL;DR

VIS is a high-resolution visible imager designed for the Euclid space mission, enabling precise weak lensing measurements and creating a valuable legacy dataset of deep, wide-area extragalactic imaging.

Contribution

This paper details the design, capabilities, and expected scientific impact of the VIS instrument for the Euclid mission, including its imaging performance and survey scope.

Findings

VIS will image in a single r+i+z band from 550-900 nm.

It will reach a depth of mAB=24.5 (10sigma) for sources ~0.3 arcsec.

VIS will cover 15,000 deg2 for cosmic shear measurements.

Abstract

Euclid-VIS is the large format visible imager for the ESA Euclid space mission in their Cosmic Vision program, scheduled for launch in 2020. Together with the near infrared imaging within the NISP instrument, it forms the basis of the weak lensing measurements of Euclid. VIS will image in a single r+i+z band from 550-900 nm over a field of view of ~0.5 deg2. By combining 4 exposures with a total of 2260 sec, VIS will reach to deeper than mAB=24.5 (10sigma) for sources with extent ~0.3 arcsec. The image sampling is 0.1 arcsec. VIS will provide deep imaging with a tightly controlled and stable point spread function (PSF) over a wide survey area of 15000 deg2 to measure the cosmic shear from nearly 1.5 billion galaxies to high levels of accuracy, from which the cosmological parameters will be measured. In addition, VIS will also provide a legacy dataset with an unprecedented combination of spatial resolution, depth and area covering most of the extra-Galactic sky. Here we will present the results of the study carried out by the Euclid Consortium during the period up to the Critical Design Review.