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arXiv · 1505.04332

An Updated Wing TiO Sensitive Index for Classification of M-Type Stars

F. Azizi·M. T. Mirtorabi
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Abstract

By careful searching of synthetic and observed spectra in a sample of cool giant and supergiant stars, we have updated the continuum band-passes of near-infrared Wing three filter system. This photometric system measures the strength of Titanium Oxide (TiO) absorption in Near-Infrared (NIR) at 719 nm. We show that new reference continuum band-passes are essentially free from molecular absorptions and the updated TiO-index defines the temperature variation in a sample of cool giants with less scatter. A TiO-index vs. effective temperature calibration is derived based on new continuum band-passes.

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F. Azizi, M. T. Mirtorabi. 2015-05-16. An Updated Wing TiO Sensitive Index for Classification of M-Type Stars. https://doi.org/10.1007/s10509-015-2366-8

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