Abstract
Radiation absorption by the CaH and VO molecular band systems in atmospheres of spectral type M dwarf stars is simulated. These bands form visible spectral details. The calculations involve detailed lists of lines calculated by different investigators. For the CaH molecule, we investigated the dependence of the calculated synthetic spectra on the adopted dissociation potential. The energy distributions in spectra of the 2MASS2242-2859 (M5.5 V) and SIPS2039-1126 (M7 IV-V) stars are reproduced. It is shown that the observed energy distributions can be confidently described by theoretical spectra calculated for model atmospheres with T eff/lgg/[Fe/H] = 3000/4.5/0 and 2700/4.5/0, respectively. These estimates are consistent with other known results.
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Original Russian Text © Ya.V. Pavlenko, M. Schmidt, 2015, published in Kinematika i Fizika Nebesnykh Tel, 2015, Vol. 31, No. 2, pp. 59–72.
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Pavlenko, Y.V., Schmidt, M. Systems of VO and CaH molecule bands in spectra of spectral type M stars. Kinemat. Phys. Celest. Bodies 31, 90–99 (2015). https://doi.org/10.3103/S0884591315020051
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DOI: https://doi.org/10.3103/S0884591315020051