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arXiv · 1412.1109

A flux calibration device for the SuperNova Integral Field Spectrograph (SNIFS)

Simona Lombardo·Greg Aldering·Akos Hoffmann·Marek Kowalski·Daniel Kuesters·Klaus Reif·Mickael Rigault
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Abstract

Observational cosmology employing optical surveys often require precise flux calibration. In this context we present SNIFS Calibration Apparatus (SCALA), a flux calibration system developed for the SuperNova Integral Field Spectrograph (SNIFS), operating at the University of Hawaii 2.2 m telescope. SCALA consists of a hexagonal array of 18 small parabolic mirrors distributed over the face of, and feeding parallel light to, the telescope entrance pupil. The mirrors are illuminated by integrating spheres and a wavelength-tunable (from UV to IR) light source, generating light beams with opening angles of 1 degree. These nearly parallel beams are flat and flux-calibrated at a subpercent level, enabling us to calibrate our "telescope + SNIFS system" at the required precision.

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Simona Lombardo, Greg Aldering, Akos Hoffmann, Marek Kowalski, Daniel Kuesters, Klaus Reif, Mickael Rigault. 2014-11-12. A flux calibration device for the SuperNova Integral Field Spectrograph (SNIFS). https://doi.org/10.1117/12.2055066

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