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arXiv · 1807.07402

The MICADO first light imager for ELT: its astrometric performance

J. -U. Pott·G. Rodeghiero·H. Riechert·D. Massari·M. Fabricius·C. Arcidiacono·R. I. Davies
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Abstract

We report on our ongoing efforts to ensure that the MICADO NIR imager reaches differential absolute (often abbreviated: relative) astrometric performance limited by the SNR of typical observations. The exceptional 39m diameter collecting area in combination with a powerful multi-conjugate adaptive optics system (called MAORY) brings the nominal centroiding error, which scales as FWHM/SNR, down to a few 10 uas. Here we show that an exceptional effort is needed to provide a system which delivers adequate and calibrateable astrometric performance over the full field of view (up to 53 arcsec diameter).

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J. -U. Pott, G. Rodeghiero, H. Riechert, D. Massari, M. Fabricius, C. Arcidiacono, R. I. Davies. 2018-07-19. The MICADO first light imager for ELT: its astrometric performance. https://arxiv.org/abs/1807.07402

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