Orbital and atmospheric parameters of two wide O-type subdwarf binaries: BD−11o162 and Feige 80

Vista sencilla de ítem
dc.contributor.authorMolina, Francisco
dc.contributor.authorVos, Joris
dc.contributor.authorNémeth, Péter
dc.contributor.authorØstensen, Roy
dc.contributor.authorVuković, Maja
dc.contributor.authorTkachenko, Andrew
dc.contributor.authorVan Winckel, Hans
dc.date.accessioned2022-11-30T02:46:37Z
dc.date.available2022-11-30T02:46:37Z
dc.date.issued2022
dc.description.abstractContext. There are 23 long-period binary systems discovered to date that contain a B-type hot subdwarf whose orbital parameters have been fully solved. They evolve into O-type subdwarfs (sdO) once the helium burning transitions from the core to the He shell. Their study will help constraint parameters on the formation and evolution of these binaries and explain some of their puzzling features. Aims. In this study, we aim to solve orbital and atmospheric parameters of two long-period sdO binaries and, for the first time, investigate the chemical composition of their main-sequence (MS) companions. Methods. HERMES high-resolution spectra are used to obtain radial velocities and solve their orbits. The GSSP code is used to derive the atmospheric parameters and photospheric chemical abundances of the MS companions. Stellar evolution models (MIST) are fitted to the companion atmospheric parameters to derive masses. Results. The orbital and atmospheric parameters have been fully solved. Masses of the companions and the sdOs were obtained. The photospheric chemical abundances of the MS stars for elements with available lines in the optical range have been derived. They match general trends expected from Galactic chemical evolution but show a depletion of yttrium in both systems and an enrichment of carbon in the BD−11o162 MS. Conclusions. In the bimodal period-eccentricity diagram, the orbital parameters indicate that Feige 80 matches the same correlation as the majority of the systems. The analysis suggests that Feige 80 has a canonical subdwarf mass and followed a standard formation channel. However, BD−11o162 is an exceptional system with a lower mass. It also shows a C overabundance, which could be caused by a higher progenitor mass. The Y depletion in the MS companions could indicate the existence of a circumbinary disk in these systems’ pasts. Nevertheless, a chemical analysis of a larger sample is necessary to draw strong conclusions.en_ES
dc.facultadFacultad de Cienciasen_ES
dc.file.nameMolina_Orb2022.pdf
dc.identifier.doihttps://doi.org/10.1051/0004-6361/202141220
dc.identifier.urihttp://repositoriobibliotecas.uv.cl/handle/uvscl/7438
dc.languageen
dc.publisherEuropean Southern Observatory (ESO)
dc.rights© ESO 2021
dc.sourceAstronomy & Astrophysics
dc.subjectSTARS: EVOLUTIONen_ES
dc.subjectSTARS: FUNDAMENTAL PARAMETERSen_ES
dc.subjectSUBDWARFSen_ES
dc.subjectBINARIES: SPECTROSCOPICen_ES
dc.titleOrbital and atmospheric parameters of two wide O-type subdwarf binaries: BD−11o162 and Feige 80
dc.typeArticulo
uv.departamentoInstituto de Fisica y Astronomia

Archivos

Bloque original
Mostrando 1 - 1 de 1
Miniatura
Nombre:
Molina_Orb2022.pdf
Tamaño:
2.12 MB
Formato:
Adobe Portable Document Format
Descargar

Colecciones

Artículos investigadores UV