ERIS: revitalising an adaptive optics instrument for the VLT

TL;DR

ERIS is a new adaptive optics instrument for the VLT that enhances imaging and spectroscopy, replacing older instruments and offering improved performance for astronomical studies of the Galactic Center, exoplanets, and distant galaxies.

Contribution

This paper introduces the ERIS instrument, detailing its design, expected performance, and advancements over previous instruments for the VLT.

Findings

Enhanced diffraction-limited imaging and spectroscopy capabilities.

Potential to outperform JWST in certain observational regimes.

Improved wavefront sensing and adaptive optics performance.

Abstract

ERIS is an instrument that will both extend and enhance the fundamental diffraction limited imaging and spectroscopy capability for the VLT. It will replace two instruments that are now being maintained beyond their operational lifetimes, combine their functionality on a single focus, provide a new wavefront sensing module that makes use of the facility Adaptive Optics System, and considerably improve their performance. The instrument will be competitive with respect to JWST in several regimes, and has outstanding potential for studies of the Galactic Center, exoplanets, and high redshift galaxies. ERIS had its final design review in 2017, and is expected to be on sky in 2020. This contribution describes the instrument concept, outlines its expected performance, and highlights where it will most excel.