Temperature and metallicity scale of cool giants

We present here quantitative diagnostic tools for cool giants that employ low-resolution near-infrared spectroscopy in the K band for stellar population studies. In this study, a total of 260 cool giants (177 stars observed with X-shooter and 83 stars observed with NIFS) are used covering a wider metallicity range than in earlier works. We measure equivalent widths of some of the selected important K-band spectral features like NaI, FeI, and ^12^CO after degrading the spectral resolution (R~1200) to investigate the spectral behaviour with fundamental parameters (e.g. effective temperature and metallicity). We derive empirical relations to measure effective temperature using the ^12^CO first-overtone band at 2.29 and 2.32{mu}m and show a detailed quantitative metallicity dependence of these correlations. We find that the empirical relations based on solar-neighborhood stars can incorporate large uncertainty in evaluating T_eff_ for metal-poor or metal-rich stars. Furthermore, we explore all the spectral lines to establish the empirical relation with metallicity and find that the quadratic fit of the combination of NaI and ^12^CO at 2.29{mu}m lines yields a reliable empirical relation at [Fe/H]~~0.0dex.

Cone search capability for table J/MNRAS/501/4596/table1 (Fundamental parameters and measured EWs of the sample)

Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/MNRAS/501/4596
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/501/4596
Related Identifier http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/501/4596
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/MNRAS/501/4596
Creator Ghosh S.; Ojha D.K.; Ninan J.P.
Publisher CDS
Publication Year 2023
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Galactic and extragalactic Astronomy; Interdisciplinary Astronomy; Natural Sciences; Observational Astronomy; Physics; Stellar Astronomy