Empirical Temperature- and Extinction-dependent Extinction Coefficients for the GALEX, Pan-STARRS 1, Gaia, SDSS, 2MASS, and WISE Passbands

Abstract We have obtained accurate dust reddening from the far-ultraviolet to the mid-infrared for up to 5 million stars by the star-pair algorithm based on LAMOST stellar parameters along with Galaxy Evolution Explorer, Pan-STARRS 1, Gaia, Sloan Digital Sky Survey, Two Micron All Sky Survey, and Wide-field Infrared Survey Explorer photometric data. The typical errors are between 0. 01 and 0. 03 mag for most colors. We derived the empirical reddening coefficients for 21 colors both in the traditional (single-valued) way and as a function of T eff and E (B − V) by using the largest samples of accurate reddening measurements, together with the extinction values from Schlegel et al. The corresponding extinction coefficients have also been obtained. The results are compared with model predictions and generally in good agreement. Comparisons with measurements in the literature show that the T eff - and E (B − V) -dependent coefficients explain the discrepancies between different measurements naturally, i. e. , using sample stars of different temperatures and reddening. Our coefficients are mostly valid in the extinction range of 0–0. 5 mag and the temperature range of 4000–10, 000 K. We recommend that the new T eff - and E (B − V) -dependent reddening and extinction coefficients should be used in the future. A Python package is also provided for the usage of the coefficients (https: //github. com/vnohhf/extinctioncoeffcient/).