Speaker
Description
M dwarfs have become an increasingly interesting target in the search for exoplanets. This is due to their small radii and low temperature which makes finding planets via both radial and transit methods easier. M dwarfs are however know to be tricky targets. The best option we have to characterise their atmospheres is using spectroscopy. This is not an easy task. M dwarf spectra are filled with molecular lines due to molecules formed in the cool atmosphere. Many spectroscopic surveys of M dwarfs are under way or are planned. Improving models used in spectroscopy of M dwarfs is therefore vital.
One assumption often made in models is Local Thermodynamical Equilibrium (LTE). This assumption does not always hold. Deviations from LTE (non-LTE) has been investigated for multiple elements for FGK stars but not for M dwarfs. We present non-LTE results in the parameter range of M dwarfs for potassium and iron. This was done by generating synthetic spectra in LTE and non-LTE using a grid of departure coefficients and compare these. We find an insignificant difference for iron and a difference for potassium corresponding to a difference in abundance of up to 0.2 dex. Work on other elements are in progress.
