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arXiv · 1207.2472

Characterizing the red optical sky background fluctuations from narrow-band imaging

M. Puech·H. Flores·Y. B. Yang·M. Rodrigues·T. Gonçalves·F. Hammer·K. Disseau
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Abstract

The detection and characterization of the physical properties of very distant galaxies will be one the prominent science case of all future Extremely Large Telescopes, including the 39m E-ELT. Multi-Object Spectroscopic instruments are potentially very important tools for studying these objects, and in particular fiber-based concepts. However, detecting and studying such faint and distant sources will require subtraction of the sky background signal (i.e., between OH airglow lines) with an accuracy of ~1%. This requires a precise and accurate knowledge of the sky background temporal and spatial fluctuations. Using FORS2 narrow-band filter imaging data, we are currently investigating what are the fluctuations of the sky background at ~9000A. We present preliminary results of sky background fluctuations from this study over spatial scales reaching ~4 arcmin, as well as first glimpses into the temporal variations of such fluctuations over timescales of the order of the hour. This study (and other complementary on-going studies) will be essential in designing the next-generation fiber-fed instruments for the E-ELT.

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M. Puech, H. Flores, Y. B. Yang, M. Rodrigues, T. Gonçalves, F. Hammer, K. Disseau. 2012-07-10. Characterizing the red optical sky background fluctuations from narrow-band imaging. https://doi.org/10.1117/12.925897

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