Astrophysical Parameters from Gaia DR2, 2MASS & AllWISE
  Stellar physical and dynamical properties are essential knowledge to
understanding the structure, formation, and evolution of our Galaxy. We
produced an all-sky uniformly derived catalog of stellar astrophysical
parameters (APs; age, mass, temperature, bolometric luminosity, distance, dust
extinction) to give insight into the physical properties of Milky-Way stars.
Exploiting the power of multi-wavelength and multi-survey observations from
Gaia DR2 parallaxes and integrated photometry along with 2MASS and AllWISE
photometry, we introduce an all-sky uniformly derived catalog of stellar
astrophysical parameters, including dust extinction (A0) and average grain size
(R0) along the line of sight, for 123,097,070 stars. In contrast with previous
works, we do not use a Galactic model as prior in our analysis. We validate our
results against other literature (e.g., benchmark stars, interferometry,
Bayestar, StarHorse). The limited optical information in the Gaia photometric
bands or the lack of ultraviolet or spectroscopic information renders the
chemistry inference prior dominated. We demonstrate that Gaia parallaxes bring
sufficient leverage to explore the detailed structures of the interstellar
medium in our Milky Way. In Gaia DR3, we will obtain the dispersed optical
light information to break through some limitations of this analysis, allowing
us to infer stellar chemistry in particular. Gaia promises us data to construct
the most detailed view of the chemo-dynamics of field star populations in our
Galaxy.
  Our catalog is available from GAVO at
http://dc.g-vo.org/tableinfo/gdr2ap.main (soon Gaia Archive and VizieR)
