FEDReD II : 3D Extinction Map with 2MASS and Gaia DR2 data

TL;DR

This paper presents a detailed 3D interstellar extinction map of the Milky Way disk using a Bayesian deconvolution method applied to 2MASS and Gaia DR2 data, revealing structures like bubbles and the local arm.

Contribution

It introduces FEDReD II, a novel Bayesian deconvolution algorithm that maps extinction in 3D beyond Gaia parallax limits, utilizing combined near-infrared and Gaia data.

Findings

Mapped the Galactic disk's extinction up to 7 kpc from the Sun.

Revealed large structures such as bubbles and the butterfly pattern.

Provided detailed extinction data for over 5.6 million stars.

Abstract

Aims. We aim to map the 3D distribution of the interstellar extinction of the Milky Way disk up to distances larger than those probed with the Gaia parallax alone. Methods. We apply the FEDReD (Field Extinction-Distance Relation Deconvolver) algorithm to the 2MASS near-infrared photometry together with the Gaia DR2 astrometry and photometry. This algorithm uses a Bayesian deconvolution approach, based on an empirical HR-diagram representative of the local thin disk, in order to map the extinction as a function of distance of various fields of view. Results. We analysed more than 5.6 million stars to obtain an extinction map of the entire Galactic disk within $|b|<0.24^{\circ}$. This map provides information up to $5~\mathrm{kpc}$ in the direction of the Galactic centre and at more than $7~\mathrm{kpc}$ in the direction of the anticentre. This map reveals the complete shape of structures known locally, such as the Vela complex or the split of the local arm. Furthermore our extinction map shows many large "clean bubbles" especially one in the Sagittarius -- Carina complex, and four others which define a structure that we nickname the butterfly.