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arXiv · 1612.08298

A New Titanium Oxide Index in Visual Band

Bahar Bidaran·Mohammad Taghi Mirtorabi·Fatemeh Azizi
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Abstract

We introduce a new color index consisting of two spectral band width to measure TiO absorption band strength centered at 567 nm. Based on the most up-to-date line list for TiO we regenerate a grid of synthesized spectra and investigate the temperature sensitivity of the index. The new index behave similar to older Wing TiO-index where itdecreas emonotonically from coolest atmosphere with Teff =2800 up to Teff =4000 where the TiO molecules disassociate. To further examine the feasibility of the new index we reproduce the calibration using a list of observed high resolution spectra and found similar results. This index extend TiO absorption band capability to measure effective temperature of late K to M stars to visual spectrum where it is more accessible to small telescopes for long term dedicated observation.

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Bahar Bidaran, Mohammad Taghi Mirtorabi, Fatemeh Azizi. 2016-12-25. A New Titanium Oxide Index in Visual Band. https://doi.org/10.1093/mnras%2Fstw051

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