From the bulge to the outer disc: StarHorse stellar parameters, distances, and extinctions for stars in APOGEE DR16 and other spectroscopic surveys^⋆

¹ Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany
e-mail: aqueiroz@aip.de
² Laboratório Interinstitucional de e-Astronomia – LIneA, Rua Gal. José Cristino 77, Rio de Janeiro, RJ 20921-400, Brazil
³ Institut de Ciències del Cosmos, Universitat de Barcelona (IEEC-UB), Carrer Martí i Franquès 1, 08028 Barcelona, Spain
⁴ Instituto de Física, Universidade Federal do Rio Grande do Sul, Caixa Postal 15051, Porto Alegre, RS 91501-970, Brazil
⁵ School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
⁶ Centro de Astrofísica da Universidade do Porto, Rua das Estrelas 4150-762, Porto, Portugal
⁷ Department of Astronomy, Universidade de São Paulo, São Paulo 05508-090, Brazil
⁸ Departamento de Ciencias Fisicas, Facultad de Ciencias Exactas, Universidad Andres Bello, Av. Fernandez Concha 700, Las Condes, Santiago, Chile
⁹ Millennium Institute of Astrophysics, Av. Vicuna Mackenna 4860, 782-0436 Santiago, Chile
¹⁰ Vatican Observatory, V00120 Vatican City State, Italy
¹¹ Instituto de Astrofísica de Canarias (IAC), 38205 La Laguna, Tenerife, Spain
¹² Universidad de La Laguna (ULL), Departamento de Astrofísica, 38206 La Laguna, Tenerife, Spain
¹³ Observatoire de la Côte d’Azur, Laboratoire Lagrange, 06304 Nice Cedex 4, France
¹⁴ The Carnegie Observatories, 813 Santa Barbara Street, Pasadena, CA 91101, USA
¹⁵ Department of Physics and JINA Center for the Evolution of the Elements, University of Notre Dame, Michigan State University, Notre Dame, IN 46556, USA
¹⁶ Apache Point Observatory, PO Box 59, Sunspot, NM 88349, USA
¹⁷ Sternberg Astronomical Institute, Moscow State University, Moscow, Russia
¹⁸ Department of Physics and Astronomy, University of Utah, 115 S. 1400 E., Salt Lake City, UT 84112, USA
¹⁹ University of Arizona, Tucson, AZ 85719, USA
²⁰ Observat’orio Nacional, Sao Cristóvao, Rio de Janeiro, Brazil
²¹ Institut Utinam, CNRS UMR 6213, Université Bourgogne-Franche-Comté, OSU THETA Franche-Comté, Observatoire de Besançon, BP 1615, 25010 Besançon Cedex, France
²² Department of Physics & Astronomy, Texas Christian University, Fort Worth, TX 76129, USA
²³ Instituto de Astrofísica, Pontificia Universidad Católica de Chile, Av. Vicuna Mackenna 4860, 782-0436 Macul, Santiago, Chile
²⁴ Instituto de Astronomía y Ciencias Planetarias, Universidad de Atacama, Copayapu 485, Copiapó, Chile
²⁵ Department of Astronomy, University of Virginia, Charlottesville, VA 22904-4325, USA
²⁶ Center for Astrophysical Sciences, Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218, USA
²⁷ Centro de Astronomía (CITEVA), Universidad de Antofagasta, Avenida Angamos 601, Antofagasta 1270300, Chile
²⁸ Departamento de Física, Facultad de Ciencias, Universidad de La Serena, Cisternas 1200, La Serena, Chile
²⁹ Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195, USA
³⁰ Center for Astrophysics and Space Astronomy, Department of Astrophysical and Planetary Sciences, University of Colorado, 389 UCB, Boulder, CO 80309-0389, USA

Received: 19 December 2019
Accepted: 18 April 2020

Abstract

We combine high-resolution spectroscopic data from APOGEE-2 survey Data Release 16 (DR16) with broad-band photometric data from several sources as well as parallaxes from Gaia Data Release 2 (DR2). Using the Bayesian isochrone-fitting code StarHorse, we derived the distances, extinctions, and astrophysical parameters for around 388 815 APOGEE stars. We achieve typical distance uncertainties of ∼6% for APOGEE giants, ∼2% for APOGEE dwarfs, and extinction uncertainties of ∼0.07 mag, when all photometric information is available, and ∼0.17 mag if optical photometry is missing. StarHorse uncertainties vary with the input spectroscopic catalogue, available photometry, and parallax uncertainties. To illustrate the impact of our results, we show that thanks to Gaia DR2 and the now larger sky coverage of APOGEE-2 (including APOGEE-South), we obtain an extended map of the Galactic plane. We thereby provide an unprecedented coverage of the disc close to the Galactic mid-plane (|Z_Gal| < 1 kpc) from the Galactic centre out to R_Gal ∼ 20 kpc. The improvements in statistics as well as distance and extinction uncertainties unveil the presence of the bar in stellar density and the striking chemical duality in the innermost regions of the disc, which now clearly extend to the inner bulge. We complement this paper with distances and extinctions for stars in other public released spectroscopic surveys: 324 999 in GALAH DR2, 4 928 715 in LAMOST DR5, 408 894 in RAVE DR6, and 6095 in GES DR3.