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arXiv · 1406.6059

Correcting for Telluric Absorption: Methods, Case Studies, and Release of the TelFit Code

Kevin Gullikson·Sarah Dodson-Robinson·Adam Kraus
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Abstract

Ground-based astronomical spectra are contaminated by the Earth's atmosphere to varying degrees in all spectral regions. We present a Python code that can accurately fit a model to the telluric absorption spectrum present in astronomical data, with residuals of $\sim 3-5\%$ of the continuum for moderately strong lines. We demonstrate the quality of the correction by fitting the telluric spectrum in a nearly featureless A0V star, HIP 20264, as well as to a series of dwarf M star spectra near the 819 nm sodium doublet. We directly compare the results to an empirical telluric correction of HIP 20264 and find that our model-fitting procedure is at least as good and sometimes more accurate. The telluric correction code, which we make freely available to the astronomical community, can be used as a replacement for telluric standard star observations for many purposes.

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Kevin Gullikson, Sarah Dodson-Robinson, Adam Kraus. 2014-06-23. Correcting for Telluric Absorption: Methods, Case Studies, and Release of the TelFit Code. https://doi.org/10.1088/0004-6256/148/3/53

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