Isochrone ages for ~3 million stars with the second Gaia data release

Overview The catalogue of ages, distances and extinctions associated with the publication Sanders & Das (2018) We provide a catalogue of the combined results from all surveys complete with the Gaia DR2 source_id for each entry. We provide a full description of the columns (including their units) in Table B1 of Sanders & Das (2018) -- listed below. For each survey, we include a unique identifier (APOGEE: APOGEE_ID, LAMOST: obsid, RAVE:raveid, GES:CNAME, GALAH: sobject_id, SEGUE: specobjid) and we provide a field survey with a string detailing which survey the entry comes from. Note that we have not removed duplicate stars that were observed by two separate surveys (e.g. RAVE and RAVE-On). For each star we include the cross-matched Gaia DR2 source_id, the angular separation of the cross-match and the photometric bands used in the pipeline. The table is saved as an astropy table (The Astropy Collaboration et al. 2018) in hdf format, and can be simply read with from astropy.table import Table; data = Table.read(’file’);. A description of the column and structure of the table is available in data.meta[’COMMENT’]. Table B1 from Sanders & Das (2018): Format of provided catalogue. We give the names, description, and unit of each provided quantity. Name Description Unit survey String describing the spectroscopic survey from which the entry derives -- APOGEE, GALAH, GES, RAVEON, RAVEDR5, LAMOST, SEGUE - raveid Unique ID for the RAVE (and RAVE-ON) catalogue - APOGEE_ID Unique ID for the APOGEE catalogue - obsid Unique ID for the LAMOST catalogue - sobject_id Unique ID for the GALAH catalogue - CNAME Unique ID for the GES catalogue - specobjid Unique ID for the SEGUE catalogue - source_id Cross-matched Gaia DR2 source ID - angular_separation On-sky separation between spectroscopic catalogue entry and Gaia DR2 cross-match (epoch corrected if proper motion has been considered) arcsec ra Right ascension from spectroscopic catalogue degree dec Declination from spectroscopic catalogue degree mag_use Comma-separated string giving photometry used in pipeline: J, H, K are 2MASS bands, G, GBP, GRP are Gaia bands, gP, rP, iP are Pan-STARRS bands, g, r, i are SDSS bands, Jv, Hv, Kv are VISTA bands - Primary outputs Name Description Unit dm Distance modulus mag dist Distance kpc par Parallax (not Gaia DR2 parallax) mas log10_age Base-10 logarithm of age log10(Gyr) mass (Initial) Mass M☉ Z Metallicity dex log10_av Base-10 logarithm of V-band extinction log10(mag) log10_teff Base-10 logarithm of effective temperature log10(K) logg Surface gravity log10(cm/s²) Auxiliary outputs Name Description Unit l Galactic longitude rad b Galactic latitude rad s Distance derived from dm column kpc vlos Line-of-sight velocity km/s mu_l Proper motion in Galactic longitude mas/yr mu_b Proper motion in Galactic latitude mas/yr R Galactocentric cylindrical polar radius kpc phi Galactocentric cylindrical polar angle (zero at solar position increasing in direction opposite to solar azimuthal velocity) rad z Galactic height kpc vR Galactocentric cylindrical radial velocity km/s vphi Galactocentric azimuthal velocity (positive for Sun and decreasing phi) km/s vz Galactocentric vertical velocity km/s JR Radial action kpc km/s Lz z-component of angular momentum (positive for Sun) kpc km/s Jz Vertical action kpc km/s Rc Galactocentric radius of circular orbit with angular momentum Lz kpc *_err Corresponding uncertainty for each field - **corr Correlations in derived quantities - Flags Name Description Unit flag Non-zero if pipeline has failed (see text for meaning of each value) - duplicated 1 if duplicate Gaia source_id (see text for how we select the source to keep) - best 1 if flag=0, duplicated=0 and valid Gaia source_id -