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arXiv · 1008.3419

Synthesising, using, and correcting for telluric features in high-resolution astronomical spectra

A. Seifahrt·H. U. Käufl·G. Zängl·J. L. Bean·M. J. Richter·R. Siebenmorgen
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Abstract

We present a technique to synthesise telluric absorption and emission features both for in-situ wavelength calibration and for their removal from astronomical spectra. While the presented technique is applicable for a wide variety of optical and infrared spectra, we concentrate in this paper on selected high-resolution near-infrared spectra obtained with the CRIRES spectrograph to demonstrate its performance and limitation. We find that synthetic spectra reproduce telluric absorption features to about 2%, even close to saturated line cores. Thus, synthetic telluric spectra could be used to replace the observation of telluric standard stars, saving valuable observing time. This technique also provides a precise in-situ wavelength calibration, especially useful for high-resolution near-infrared spectra in the absence of other calibration sources.

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A. Seifahrt, H. U. Käufl, G. Zängl, J. L. Bean, M. J. Richter, R. Siebenmorgen. 2010-08-20. Synthesising, using, and correcting for telluric features in high-resolution astronomical spectra. https://doi.org/10.1051/0004-6361/200913782

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