MIRI Coronagraphy Calibration Status

The overall calibration status and estimated accuracy of MIRI coronagraphy are described in this article; please also see the article on known issues affecting MIRI coronagraphic data.

Photometric calibration

Photometric calibration: Uncertainties are of order 3% or better at all wavelengths, due to variation in measured values from one standard star to another. The telescope/instrument stability are better than 0.5% over time based on repeated measurements of one star in F770W. The coronagraphs are subject to the same time-dependent decline in sensitivity as the imager. This effect is primarily observed at long wavelengths, and only affects the F1550C and F2300C coronagraphic filters. A time-dependent sensitivity correction was implemented in September 2023, and its accuracy is regularly monitored through the MIRI photometric calibration program.

Notable updates

  • Added links to the time-dependent sensitivity decline
Originally published