The RAVE-on catalog of stellar atmospheric parameters and chemical abundances for chemo-dynamic studies in the Gaia era

TL;DR

This paper presents RAVE-on, a comprehensive re-analysis of RAVE spectra using The Cannon, providing precise stellar parameters and chemical abundances for over half a million stars, enhancing chemo-dynamic studies in the Gaia era.

Contribution

It introduces a data-driven re-analysis of RAVE spectra with The Cannon, improving parameter and abundance precision for large stellar samples in conjunction with Gaia data.

Findings

Derived effective temperatures, surface gravities, and abundances for up to seven elements.

Achieved a typical abundance precision of 0.07 dex.

Produced the most powerful chemo-dynamic dataset for Milky Way studies.

Abstract

The orbits, atmospheric parameters, chemical abundances, and ages of individual stars in the Milky Way provide the most comprehensive illustration of galaxy formation available. The Tycho-Gaia Astrometric Solution (TGAS) will deliver astrometric parameters for the largest ever sample of Milky Way stars, though its full potential cannot be realized without the addition of complementary spectroscopy. Among existing spectroscopic surveys, the RAdial Velocity Experiment (RAVE) has the largest overlap with TGAS ($\gtrsim$200,000 stars). We present a data-driven re-analysis of 520,781 RAVE spectra using The Cannon. For red giants, we build our model using high-fidelity APOGEE stellar parameters and abundances for stars that overlap with RAVE. For main-sequence and sub-giant stars, our model uses stellar parameters from the K2/EPIC. We derive and validate effective temperature $T_{\rm eff}$, surface gravity $\log{g}$, and chemical abundances of up to seven elements (O, Mg, Al, Si, Ca, Fe, Ni). We report a total of 1,685,851 elemental abundances with a typical precision of 0.07 dex, a substantial improvement over previous RAVE data releases. The synthesis of RAVE-on and TGAS is the most powerful data set for chemo-dynamic analyses of the Milky Way ever produced.