2017/10/31 by A. B. A. Queiroz, Anna B. A. Queiroz, F. Anders +24 · 227 citations
Physics and Astronomy · #Asteroseismology #Astronomy #Astronomy and Astrophysical Research #Astrophysics #Galaxy #Gamma-ray bursts and supernovae #Milky Way #Parallax #Physics #Population #Stars #Stellar, planetary, and galactic studies #astro-ph.GA #astro-ph.IM #astro-ph.SR
paper · pdf · open access · doi:10.1093/mnras/sty330
published in Monthly Notices of the Royal Astronomical Society 476(2), 2556-2583 (Oxford University Press) · 21 pages, 12 figures, accepted
arxiv created 2018/02/02 · openalex publication_date 2018/02/07 · arxiv updated 2018/02/28 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Understanding the formation and evolution of our Galaxy requires accurate distances, ages, and chemistry for large populations of field stars. Here, we present several updates to our spectrophotometric distance code, which can now also be used to estimate ages, masses, and extinctions for individual stars. Given a set of measured spectrophotometric parameters, we calculate the posterior probability distribution over a given grid of stellar evolutionary models, using flexible Galactic stellar-population priors. The code (called StarHorse) can accommodate different observational data sets, prior options, partially missing data, and the inclusion of parallax information into the estimated probabilities. We validate the code using a variety of simulated stars as well as real stars with parameters determined from asteroseismology, eclipsing binaries, and isochrone fits to star clusters. Our main goal in this validation process is to test the applicability of the code to field stars with known Gaia-like parallaxes. The typical internal precisions (obtained from realistic simulations of an APOGEE+Gaia-like sample) are |≃ 8 \rmper cent| in distance, |≃ 20 \rmper cent| in age, |≃ 6 \rmper cent| in mass, and ≃ 0.04 mag in AV. The median external precision (derived from comparisons with earlier work for real stars) varies with the sample used, but lies in the range of |≃ [0,2] \rmper cent| for distances, |≃ [12,31] \rmper cent| for ages, |≃ [4,12] \rmper cent| for masses, and ≃ 0.07 mag for AV. We provide StarHorse distances and extinctions for the APOGEE DR14, RAVE DR5, GES DR3, and GALAH DR1 catalogues.