# 10.4.5 Astrophysical parameters

## Extinction

First tests work on low extinction stars, checking that indeed their extinction values and associated uncertainties are consistent with being low. For this we use a selection in Galactic latitude $b>50$${}^{\circ}$where the extinction is expected to be small and at most $E(B-V)=0.05$ and stars within the local bubble with parallax$>$20 mas (50 pc), where there is no significant extinction.

We compare the Gaia DR2 extinctions to the ones provided together with APOGEE DR14 (http://www.sdss.org/dr14/data_access/value-added-catalogs/?vac_id=apogee-dr14-based-distance-estimations/).

## Temperature

Temperatures were compared with spectroscopic surveys ones: APOGEE DR14 (Holtzman et al. 2015), LAMOST DR2 (Luo et al. 2015), GALAH DR1 (Martell et al. 2017), GES DR3 (Gilmore et al. 2012).