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Description
These reddening and interstellar extinction estimates are a result of a series of studies presented in the papers 2009AstL...35..780G, 2010AstL...36..584G, 2012AstL...38...12G, 2012AstL...38...87G, 2017AstL...43..472G and finally 2017MNRAS.472.3805G and 2018MNRAS.475.1121G. The key basis of these estimates is the 3D reddening map of Gontcharov (2017AstL...43..472G, 2017PAZh...43..521G, Cat. J/PAZh/43/521). This map has been tested among eight sources of reddening and extinction estimates for nearly 60,000 Gaia DR1 TGAS main sequence stars younger than 3Gyr with a relative error of the Gaia parallax less than 0.1. The sources are tested in their ability to put the stars among the PARSEC and MIST theoretical isochrones in the Hertzsprung-Russell diagram based on the precise Gaia, Tycho-2, 2MASS and WISE photometry. The 3D reddening map of Gontcharov provides both the minimal number of outliers bluer than any reasonable isochrone and the correct number of stars younger than 3Gyr in agreement with the Besancon Galaxy model. In another test Gaia DR1 TGAS parallaxes, Tycho-2 photometry and reddening/extinction estimates from nine data sources for 38,074 giants within 415pc from the Sun are used to compare their position in the Hertzsprung-Russell diagram with theoretical estimates, which are based on the PARSEC and MIST isochrones and the TRILEGAL model of the Galaxy with its parameters being widely varied. We conclude that, again, the estimates from the 3D reddening map of Gontcharov, including the median reddening E(B-V)=0.06mag at |b|>50{deg}, give the best fit of the empirical and theoretical data with each other. Based on these studies we present here the best up-to-date reddening, extinction and extinction-to-reddening estimates for the Gaia DR1 TGAS and Hipparcos stars within 415pc from the Sun. The accuracy of the E(B-V) estimates is proved to be better than 0.04mag everywhere in this space.
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