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Metallicity measurements using atomic lines in M and K dwarf stars

Vincent M. Woolf·George Wallerstein
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Abstract

We report the first survey of chemical abundances in M and K dwarf stars using atomic absorption lines in high resolution spectra. We have measured Fe and Ti abundances in 35 M and K dwarf stars using equivalent widths measured from (lambda / Delta lambda) = 33,000 spectra. Our analysis takes advantage of recent improvements in model atmospheres of low-temperature dwarf stars. The stars have temperatures between 3300 and 4700 K, with most cooler than 4100 K. They cover an iron abundance range of -2.44 < [Fe/H] < +0.16. Our measurements show [Ti/Fe] decreasing with increasing [Fe/H], a trend similar to that measured for warmer stars where abundance analysis techniques have been tested more thoroughly. This study is a step toward the observational calibration of procedures to estimate the metallicity of low-mass dwarf stars using photometric and low-resolution spectral indices.

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Vincent M. Woolf, George Wallerstein. 2004-10-19. Metallicity measurements using atomic lines in M and K dwarf stars. https://doi.org/10.1111/j.1365-2966.2004.08515.x

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