JWST MIRI Flight Performance: Imaging

TL;DR

The paper reviews the JWST MIRI imager's performance during commissioning and science operations, confirming it meets or exceeds expectations and is poised to significantly advance mid-infrared astronomy.

Contribution

This study provides the first comprehensive assessment of MIRI imaging performance, including calibration, artifacts, and observing best practices, based on real mission data.

Findings

MIRI imager meets or exceeds pre-flight requirements

Point spread function and flux calibration are well characterized

Imaging artifacts are identified and understood

Abstract

The Mid-Infrared Instrument (MIRI) aboard the James Webb Space Telescope (JWST) provides the observatory with a huge advance in mid-infrared imaging and spectroscopy covering the wavelength range of 5 to 28 microns. This paper describes the performance and characteristics of the MIRI imager as understood during observatory commissioning activities, and through its first year of science operations. We discuss the measurements and results of the imager's point spread function, flux calibration, background, distortion and flat fields as well as results pertaining to best observing practices for MIRI imaging, and discuss known imaging artefacts that may be seen during or after data processing. Overall, we show that the MIRI imager has met or exceeded all its pre-flight requirements, and we expect it to make a significant contribution to mid-infrared science for the astronomy community for years to come.