Astrophysical Parameters from Gaia DR2, 2MASS & AllWISE

TL;DR

This paper presents a comprehensive all-sky catalog of stellar astrophysical parameters derived from Gaia DR2, 2MASS, and AllWISE data, providing new insights into the structure and composition of the Milky Way without relying on Galactic models.

Contribution

It introduces a novel, all-sky, uniformly derived catalog of stellar parameters using multi-survey data without prior Galactic models, validated against existing literature.

Findings

Catalog includes parameters for over 123 million stars.

Gaia parallaxes enable detailed interstellar medium structure analysis.

Limitations due to optical and ultraviolet data are acknowledged, with future Gaia data expected to improve chemistry inference.

Abstract

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)