2023 StarHorse results for spectroscopic surveys + Gaia DR3
StarHorse results for spectroscopic surveys + Gaia DR3: Chrono-chemical populations in the solar vicinity, the genuine thick disk, and young-alpha rich stars
Abstract
The Gaia mission has provided an invaluable wealth of astrometric data for more than a billion stars in our Galaxy. The synergy between Gaia astrometry, photometry, and spectroscopic surveys give us comprehensive information about the Milky Way. Using the Bayesian isochrone-fitting code StarHorse, we derive distances and extinctions for more than 10 million unique stars observed by both Gaia Data Release 3 as well as public spectroscopic surveys: 557 559 in GALAH+ DR3, 4 531 028 in LAMOST DR7 LRS, 347 535 in LAMOST DR7 MRS, 562 424 in APOGEE DR17, 471 490 in RAVE DR6, 249 991 in SDSS DR12 (optical spectra from BOSS and SEGUE), 67 562 in the Gaia-ESO DR3 survey, and 4 211 087 in the Gaia RVS part of Gaia DR3 release. StarHorse can extend the precision of distances and extinctions measurements where Gaia parallaxes alone would be uncertain. We use StarHorse for the first time to derive stellar age for main-sequence turnoff and subgiant branch stars (MSTO-SGB), around 2.5 million stars with age uncertainties typically around 30%, 15% for only SGB stars, depending on the resolution of the survey. With the derived ages in hand, we investigate the chemical-age relations. In particular, the α and neutron-capture element ratios versus age in the solar neighbourhood show trends similar to previous works, validating our ages. We use the chemical abundances from local subgiant samples of GALAH DR3, APOGEE DR17 and LAMOST MRS DR7 to map groups with similar chemical compositions and StarHorse ages with the dimensionality reduction technique t-SNE and the clustering algorithm HDBSCAN. We identify three distinct groups in all three samples. Their kinematic properties confirm them to be the genuine chemical thick disk, the thin disk and a considerable number of young alpha-rich stars (427), which are also a part of the delivered catalogues. We confirm that the genuine thick disk’s kinematics and age properties are radically different from those of the thin disk and compatible with high-redshift (z≈2) star-forming disks with high dispersion velocities. We also find a few extra chemical populations in the GALAH DR3, thanks to the availability of neutron-capture elements.
Data versioning:
We warn users that the data first published in this domain contained misleading age results for old stars due to a piecewise age prior for thin disk. In the v2 version of the files, ages and masses are calculated using the Gaussian age priors described in Queiroz et al. 2018. Distances, temperatures, surface gravities and extinction remain the same.
The data formats
The data is available in FITS binary file format:
- FITS: List of fits files
- HDF: tSNE-Groups.hdf5
Getting the data
Get the list of the files:
wget --no-check-certificate https://s3.data.aip.de:9000/shaqueiroz2023/list.txt
Download the data:
wget --no-check-certificate -i list.txt
- Access examples: TBD
StarHorse Data Model
The tables are in the same format described in the appendix of Queiroz et al. 2020
| Column | Description | Unit |
|---|---|---|
| Survey ID | General Identifier from each survey | - |
| DR3_source_id | Gaia DR3 unique ID | - |
| GLON | Galactic longitude | degrees |
| GLAT | Galactic latitude | degrees |
| mass16 | 16th percentil of marginalized PDF | Solar masses |
| mass50 | 50th percentil of marginalized PDF | Solar masses |
| mass84 | 84th percentil of marginalized PDF | Solar masses |
| teff16 | 16th percentil of marginalized PDF | Kelvins |
| teff50 | 50th percentil of marginalized PDF | Kelvins |
| teff84 | 84th percentil of marginalized PDF | Kelvins |
| logg16 | 16th percentil of marginalized PDF | dex |
| logg50 | 16th percentil of marginalized PDF | dex |
| logg84 | 84th percentil of marginalized PDF | dex |
| met16 | 16th percentil of marginalized PDF | dex |
| met50 | 50th percentil of marginalized PDF | dex |
| met84 | 84th percentil of marginalized PDF | dex |
| dist05 | 05th percentil of marginalized PDF | kpc |
| dist16 | 16th percentil of marginalized PDF | kpc |
| dist50 | 50th percentil of marginalized PDF | kpc |
| dist84 | 84th percentil of marginalized PDF | kpc |
| dist95 | 95th percentil of marginalized PDF | kpc |
| AV05 | 05th percentil of marginalized PDF | mag |
| AV16 | 16th percentil of marginalized PDF | mag |
| AV50 | 50th percentil of marginalized PDF | mag |
| AV84 | 84th percentil of marginalized PDF | mag |
| AV95 | 95th percentil of marginalized PDF | mag |
| age05 | 05th percentil of marginalized PDF | Gyr |
| age16 | 16th percentil of marginalized PDF | Gyr |
| age50 | 50th percentil of marginalized PDF | Gyr |
| age84 | 84th percentil of marginalized PDF | Gyr |
| age95 | 95th percentil of marginalized PDF | Gyr |
| StarHorse_INPUTFLAG | flag specifying input data and quality | - |
| StarHorse_OUTPUTFLAG | flag specifying StarHorse results quality | - |
| StarHorse_AGEFLAG | flag specifying age results for evolutionary stage | - |
| StarHorse_AGEINOUT | Warning on age results | - |
StarHorse Flags
Four flags accompaign the tables:
| SH_INPUTFLAGS | Description |
|---|---|
| "TEFF.." | calibrated spectroscopic parameters (e.g. TEFF) were used |
| "uncalTEFF.." | uncalibrated spectroscopic parameters (e.g. TEFF) + inflated uncertainties were used |
| "PARALLAX" | Gaia EDR3 parallaxes + recalibrated zeropoint and uncertainties were used |
| "..2mass.." | eg. 2MASS photometry was used (other photometric sets: Wise, panstarrs, SM) |
| "AV_prior" | AV prior from extinction maps or targeting was used |
| StarHorse_OUTPUTFLAGS | Description |
|---|---|
| "NEGATIVE_EXTINCTION" | "bad extinction estimates" |
| "NUMMODELS_HIGH" | " high number of stellar models compatible with observations within" |
| "NUMMODELS_LOW" | " Low number of stellar models compatible with observations within" |
| StarHorse_AGEFLAG | Description |
|---|---|
| "NOAGE" | "stars outside the main sequence turn-off range, no ages are derived" |
| "MSTO" | " Stars at the main sequence turn-off regime" |
| "SGB" | " stars at the subgiant branch regime, those have the best age estimates" |
| StarHorse_AGEINOUT | Description |
|---|---|
| "Warn_diff_inout" | "Warning for using the age results for which initial temperatures, metallicites or surface gravities deviate from input data by more than 300 K, 0.3 dex and 0.3 dex respectively." |
Citations
Refer to the following papers when describing StarHorse method: Santiago et al 2016 ; Queiroz et al 2018; Anders et al 2019
Refer to Queiroz et al. 2023 when using this data.