The GALAH survey: A catalogue of carbon-enhanced stars and CEMP candidates

Forskningsoutput: TidskriftsbidragArtikel i vetenskaplig tidskrift

Abstract

Swan bands-characteristic molecular absorption features of the C2 molecule-are a spectroscopic signature of carbon-enhanced stars. They can also be used to identify carbonenhanced metal-poor (CEMP) stars. The GALAH (GALactic Archaeology with Hermes) is a magnitude-limited survey of stars producing high-resolution, high-signal-to-noise spectra. We used 627 708 GALAH spectra to search for carbon-enhanced stars with a supervised and unsupervised classification algorithm, relying on the imprint of the Swan bands. We identified 918 carbon-enhanced stars, including 12 already described in the literature. An unbiased selection function of the GALAH survey allows us to perform a population study of carbon-enhanced stars. Most of them are giants, out of which we find 28 CEMP candidates. A large fraction of our carbon-enhanced stars with repeated observations show variation in radial velocity, hinting that there is a large fraction of variables among them. 32 of the detected stars also show strong Lithium enhancement in their spectra.

Detaljer

Författare
  • the GALAH collaboration
Enheter & grupper
Externa organisationer
  • University of Ljubljana
  • University of Sydney
  • University of New South Wales
  • Australian National University
  • Max Planck Institute for Astronomy
  • Macquarie University, Sydney
  • University of Virginia
  • University of Southern Queensland
  • Johns Hopkins University
  • Institute for Advanced Study, Princeton
  • Carnegie Observatories
  • Princeton University
  • National Institute for Astrophysics
  • INAF - Osservatorio Astronomico di Padova
Forskningsområden

Ämnesklassifikation (UKÄ) – OBLIGATORISK

  • Astronomi, astrofysik och kosmologi
  • Atom- och molekylfysik och optik

Nyckelord

Originalspråkengelska
Sidor (från-till)3196-3212
Antal sidor17
TidskriftMonthly Notices of the Royal Astronomical Society
Volym483
Utgåva nummer3
StatusPublished - 2019
PublikationskategoriForskning
Peer review utfördJa