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arXiv · 1609.05290

Revision of Stellar Intrinsic Colors in the Infrared by the Spectroscopic Surveys

Mingjie Jian·Shuang Gao·He Zhao·Biwei Jiang
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Abstract

Intrinsic colors of normal stars are derived in the popularly used infrared bands involving the 2MASS/JHKs, WISE, Spitzer/IRAC and AKARI/S9W filters. Based on three spectroscopic surveys -- LAMOST, RAVE and APOGEE, stars are classified into groups of giants and dwarfs, as well as metal-normal and metal-poor stars. An empirical analytical relation of the intrinsic color is obtained with stellar effective temperature (Teff) for each group of stars after the zero-reddening stars are selected from the blue edge in the $J-λ$ versus (Teff) diagram. It is found that metallicity has little effect on the infrared colors. In the near-infrared bands, our results agree with previous work. In addition, the color indexes H-W2 and Ks-W1 that are taken as constant to calculate interstellar extinction are discussed. The intrinsic color of M-type stars are derived separately due to lack of accurate measurement of their effective temperature.

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Mingjie Jian, Shuang Gao, He Zhao, Biwei Jiang. 2016-09-17. Revision of Stellar Intrinsic Colors in the Infrared by the Spectroscopic Surveys. https://doi.org/10.3847/1538-3881%2F153%2F1%2F5

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