Evolutionay status of Kepler red giants

Evolved cool stars have three distinct evolutionary status: shell Hydrogen-burning (RGB), core Helium and shell Hydrogen burning (RC), and double shell burning (AGB). Asteroseismology can distinguish between the RC and the other status, but distinguishing RGB and AGB has been difficult seismically and spectroscopically. The precise boundaries of different status in the HR diagram have also been difficult to establish. Aims: in this article, we present a comprehensive catalog of asteroseismic evolutionary status, RGB and RC, for evolved red giants in the Kepler field. We carefully examine boundary cases to define the lower edge of the RC phase in radius and surface gravity. We also test different published asteroseisemic methods claiming to distinguish AGB and RGB stars against a sample where AGB candidates were selected using a spectroscopic identification method. methods: we used six different seismic techniques to distinguish RC and RGB stars, and tested two proposed methods for distinguishing AGB and RGB stars. These status were compared with those inferred from spectroscopy. Results: we present consensus evolutionary status for 18784 stars out of the 30337 red giants present in the Kepler data, including 11516 stars with APOGEE spectra available. The agreement between seismic and spectroscopic classification is excellent for distinguishing RC stars, agreeing at the 94% level. Most disagreements can be traced to uncertainties in spectroscopic parameters, but some are caused by blends with background stars. We find a sharp lower boundary in surface gravity at log(g)=2.99+/-0.01 for the RC and discuss the implications. We demonstrate that asteroseismic tools for distinguishing AGB and RGB stars are consistent with spectroscopic evolutionary status at near the RC (with the asteroseismic large separation {DELTA}{NU}<=2uHz) but that the agreement between the different methods decreases rapidly as the star evolves during the AGB phase. Conclusions: this work present the most complete evolutionary status catalog for Kepler and APOGEE red giant stars. The data precisely defines the locus of RC stars in the HR diagram, an important constraint for stellar theory and stellar populations. We also demonstrate that asteroseismic tools can distinguish between AGB and RGB stars under some circumstances, which is important for the age estimation for field stars. However, we also put forward the importance of using several techniques to assess the evolutionary status determination for luminous red giants

Cone search capability for table J/A+A/697/A165/table2 (Evolutionary status (clump or RGB/AGB) of the Kepler red giant sample)

Cone search capability for table J/A+A/697/A165/table4 (Evolutionarys status (AGB/RGB) of the red giants above the clump)

Identifier
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/A+A/697/A165
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/697/A165
Related Identifier https://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/697/A165
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/A+A/697/A165
Provenance
Creator Vrard M.; Pinsonneault M.H.; Elsworth Y.; Hon M.; Kallinger T.,Kuszlewicz J.; Mosser B.; Garcia R.A.; Tayar J.; Bennett R.; Cao K.,Hekker S.; Loyer L.; Mathur S.; Stello D.
Publisher CDS
Publication Year 2025
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Natural Sciences; Observational Astronomy; Physics; Stellar Astronomy