Lithium with Machine-Learning Virtual Observatory Resource

Authors
  1. Nepal S.
  2. Guiglion G.
  3. de Jong R.S.
  4. Valentini M.
  5. Chiappini C.,Steinmetz M.
  6. Ambrosch M.
  7. Pancino E.
  8. Jeffries R.D.
  9. Bensby T.
  10. Romano D.,Smiljanic R.
  11. Dantas M.L.L.
  12. Gilmore G.
  13. Randich S.
  14. Bayo A.
  15. Bergemann M.,Franciosini E.
  16. Jimenez Esteban F.
  17. Jofre P.
  18. Morbidelli L.
  19. Sacco G.G.,Tautvaisiene G.
  20. Zaggia S.
  21. Published by
    CDS
Abstract

With its origin coming from several sources (Big Bang, stars, cosmic rays) and given its strong depletion during its stellar lifetime, the lithium element is of great interest as its chemical evolution in the Milky Way is not well understood at present. To help constrain stellar and galactic chemical evolution models, numerous and precise lithium abundances are necessary for a large range of evolutionary stages, metallicities, and Galactic volume. In the age of stellar parametrization on industrial scales, spectroscopic surveys such as APOGEE, GALAH, RAVE, and LAMOST have used data-driven methods to rapidly and precisely infer stellar labels (atmospheric parameters and abundances). To prepare the ground for future spectroscopic surveys such as 4MOST and WEAVE, we aim to apply machine learning techniques to lithium measurements and analyses. We trained a convolution neural network (CNN), coupling Gaia-ESO Survey iDR6 stellar labels (Teff, log(g), [Fe/H], and A(Li)) and GIRAFFE HR15N spectra, to infer the atmospheric parameters and lithium abundances for 40000 stars. The CNN architecture and accompanying notebooks are available online via GitHub at https://github.com/SamirNepal. We show that the CNN properly learns the physics of the stellar labels, from relevant spectral features through a broad range of evolutionary stages and stellar parameters. The lithium feature at 6707.8{AA}, is successfully singled out by our CNN, among the thousands of lines in the GIRAFFE HR15N setup. Rare objects such as lithium-rich giants are found in our sample. This level of performance is achieved thanks to a meticulously built, high-quality, and homogeneous training sample. The CNN approach is very well adapted for the next generations of spectroscopic surveys aimed at studying (among other elements) lithium, such as the 4MIDABLE-LR/HR (4MOST Milky Way disk and bulge at low and high resolution) surveys. In this context, the caveats of machine-learning applications should be appropriately investigated, along with the realistic label uncertainties and upper limits for abundances.

Keywords
  1. surveys
  2. standard-stars
  3. chemical-abundances
  4. spectroscopy
  5. effective-temperature
  6. visible-astronomy
Bibliographic source Bibcode
2023A&A...671A..61N
See also HTML
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/671/A61
IVOA Identifier IVOID
ivo://CDS.VizieR/J/A+A/671/A61
Document Object Identifer DOI
doi:10.26093/cds/vizier.36710061

Access

Web browser access HTML
http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/671/A61
https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/671/A61
http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/671/A61
IVOA Table Access TAP
http://tapvizier.cds.unistra.fr/TAPVizieR/tap
Run SQL-like queries with TAP-enabled clients (e.g., TOPCAT).
IVOA Cone Search SCS
For use with a cone search client (e.g., TOPCAT).
http://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/671/A61/table1?
https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/671/A61/table1?
http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/671/A61/table1?

History

2023-03-06T08:00:37Z
Resource record created
2023-03-06T08:00:37Z
Created
2023-05-16T07:17:38Z
Updated

Contact

Name
CDS support team
Postal Address
CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France
E-Mail
cds-question@unistra.fr