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arXiv · 1603.03865

FORS2 Rotating Flat Field Systematics Fixed -- Recent Exchange of FORS LADC Prisms Improves the Long-known Flat-fielding Problem

Henri M. J. Boffin·Sabine Moehler·Wolfram Freudling
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Abstract

For many years the FORS2 instrument has suffered from artefacts in the flat fields caused by surface inhomogeneities on the longitudinal atmospheric dispersion corrector (LADC) that affected high-precision photometric and spectroscopic measurements. Recently, the FORS LADC prisms were exchanged, and our analysis of a large number of flat fields shows that this exchange has resulted in a significant decrease in the level of small-scale artefacts.

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Henri M. J. Boffin, Sabine Moehler, Wolfram Freudling. 2016-03-12. FORS2 Rotating Flat Field Systematics Fixed -- Recent Exchange of FORS LADC Prisms Improves the Long-known Flat-fielding Problem. https://arxiv.org/abs/1603.03865

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