On the Telluric Correction of KMOS Spectra

The presence of strong absorption lines in the atmospheric transmission spectrum affects spectroscopic observations, in particular those in the near- and mid-infrared. Therefore, there is the need to correct scientific observations for this effect, a process known as telluric correction. The use of a detailed model of the atmospheric transmission spectrum brings several advantages over the method of empirically deriving corrections using observations of a telluric standard star. In this paper, we discuss and compare the two methods applied to K-band Multi-Object Spectrograph (KMOS) observations and show the improvements in the quality of the final products obtained by implementing the modelling technique offered by the ESO molecfit sky tool.
Published in The Messenger vol. 177, pp. 14-18, September 2019.