s-process enhanced stars in the LAMOST survey Virtual Observatory Resource

Authors
  1. Norfolk B.J.
  2. Casey A.R.
  3. Karakas A.I.
  4. Miles M.T.
  5. Kemp A.J.,Schlaufman K.C.
  6. Ness M.
  7. Ho A.Y.Q.
  8. Lattanzio J.C.
  9. Ji A.P.
  10. Published by
    CDS
Abstract

Here we present the discovery of 895 s-process-rich candidates from 454180 giant stars observed by the Large Sky Area Multi-Object Fibre Spectroscopic Telescope (LAMOST) using a data-driven approach. This sample constitutes the largest number of s-process enhanced stars ever discovered. Our sample includes 187 s-process-rich candidates that are enhanced in both barium and strontium, 49 stars with significant barium enhancement only and 659 stars that show only a strontium enhancement. Most of the stars in our sample are in the range of effective temperature and logg typical of red giant branch (RGB) populations, which is consistent with our observational selection bias towards finding RGB stars. We estimate that only a small fraction (~0.5 per cent) of binary configurations are favourable for s-process enriched stars. The majority of our s-process-rich candidates (95 per cent) show strong carbon enhancements, whereas only five candidates (<3 per cent) show evidence of sodium enhancement. Our kinematic analysis reveals that 97 per cent of our sample are disc stars, with the other 3 per cent showing velocities consistent with the Galactic halo. The scaleheight of the disc is estimated to be z_h_=0.634+/-0.063kpc, comparable with values in the literature. A comparison with yields from asymptotic giant branch (AGB) models suggests that the main neutron source responsible for the Ba and Sr enhancements is the ^13^C({alpha},n)^16^O reaction. We conclude that s-process-rich candidates may have received their overabundances via mass transfer from a previous AGB companion with an initial mass in the range 1-3M_{sun}_.

Keywords
  1. Giant stars
  2. Peculiar variable stars
  3. Chemically peculiar stars
  4. Astrometry
  5. Optical astronomy
  6. Trigonometric parallax
  7. Proper motions
  8. Radial velocity
  9. Effective temperature
Bibliographic source Bibcode
2019MNRAS.490.2219N
See also HTML
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/490/2219
IVOA Identifier IVOID
ivo://CDS.VizieR/J/MNRAS/490/2219

Access

Web browser access HTML
http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/490/2219
https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/490/2219
http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/490/2219
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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/MNRAS/490/2219/table1?
https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/490/2219/table1?
http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/490/2219/table1?

History

2023-03-21T12:52:00Z
Resource record created
2023-03-21T12:52:00Z
Created
2023-05-04T08:33:20Z
Updated

Contact

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