The mid-infrared instrument for the James Webb Space telescope, VII: The MIRI detectors

G. H. Rieke, M. E. Ressler, Jane E. Morrison, L. Bergeron, Patrice Bouchet, Macarena García-Marín, T. P. Greene, M. W. Regan, K. G. Sukhatme, Helen Walker

Research output: Contribution to journalArticlepeer-review

65 Scopus citations


The MIRI Si:As IBC detector arrays extend the heritage technology from the Spitzer IRAC arrays to a 1024 × 1024 pixel format. We provide a short discussion of the principles of operation, design, and performance of the individual MIRI detectors, in support of a description of their operation in arrays provided in an accompanying paper. We then describe modeling of their response. We find that electron diffusion is an important component of their performance, although it was omitted in previous models. Our new model will let us optimize the bias voltage while avoiding avalanche gain. It also predicts the fraction of the IR-active layer that is depleted (and thus contributes to the quantum efficiency) as signal is accumulated on the array amplifier. Another set of models accurately predicts the nonlinearity of the detector-amplifier unit and has guided determination of the corrections for nonlinearity. Finally, we discuss how diffraction at the interpixel gaps and total internal reflection can produce the extended cross-like artifacts around images with these arrays at short wavelengths, ∼5 μm. The modeling of the behavior of these devices is helping optimize how we operate them and also providing inputs to the development of the data pipeline.

Original languageEnglish (US)
Pages (from-to)665-674
Number of pages10
JournalPublications of the Astronomical Society of the Pacific
Issue number953
StatePublished - Jul 1 2015

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science


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