Revisiting symbiotic binaries with interferometry. I. The PIONIER archival collection

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Merc, Jaroslav, Boffin, Henri M. J.
Format: Preprint
Publié: 2025
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866915141547720704
author Merc, Jaroslav
Boffin, Henri M. J.
author_facet Merc, Jaroslav
Boffin, Henri M. J.
contents Symbiotic stars serve as exceptional laboratories for investigating mass transfer processes in binary systems. However, the dominant mechanism of mass transfer from the red giant donor to the compact accretor - typically a white dwarf or, in rare cases, a neutron star - remains unclear. It is uncertain whether it is driven primarily by the stellar wind, Roche-lobe overflow, or a combination of the two. While radii inferred from rotational velocities or spectral types suggest smaller Roche-lobe filling factors, the presence of ellipsoidal variability, presumably caused by tidally deformed giants in many symbiotic systems, indicates the opposite. Interferometric observations of symbiotic giants, combined with distance measurements provided by the Gaia mission, offer a promising avenue to resolve this discrepancy. In this first paper of the series, we (re)analyze VLTI/PIONIER observations of six symbiotic stars: AG Peg, FG Ser, ER Del, V1261 Ori, RW Hya, and V399 Pav. With the exception of the uncertain case of V399 Pav, we find that the giants in these systems remain well within their canonical Roche lobes, even in V1261 Ori and RW Hya, where ellipsoidal variability is observed. All six stars appear to be rather luminous and likely located on the asymptotic giant branch, although the possibility of some of them being at the tip of the first red giant branch cannot be ruled out.
format Preprint
id arxiv_https___arxiv_org_abs_2502_04089
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Revisiting symbiotic binaries with interferometry. I. The PIONIER archival collection
Merc, Jaroslav
Boffin, Henri M. J.
Solar and Stellar Astrophysics
Symbiotic stars serve as exceptional laboratories for investigating mass transfer processes in binary systems. However, the dominant mechanism of mass transfer from the red giant donor to the compact accretor - typically a white dwarf or, in rare cases, a neutron star - remains unclear. It is uncertain whether it is driven primarily by the stellar wind, Roche-lobe overflow, or a combination of the two. While radii inferred from rotational velocities or spectral types suggest smaller Roche-lobe filling factors, the presence of ellipsoidal variability, presumably caused by tidally deformed giants in many symbiotic systems, indicates the opposite. Interferometric observations of symbiotic giants, combined with distance measurements provided by the Gaia mission, offer a promising avenue to resolve this discrepancy. In this first paper of the series, we (re)analyze VLTI/PIONIER observations of six symbiotic stars: AG Peg, FG Ser, ER Del, V1261 Ori, RW Hya, and V399 Pav. With the exception of the uncertain case of V399 Pav, we find that the giants in these systems remain well within their canonical Roche lobes, even in V1261 Ori and RW Hya, where ellipsoidal variability is observed. All six stars appear to be rather luminous and likely located on the asymptotic giant branch, although the possibility of some of them being at the tip of the first red giant branch cannot be ruled out.
title Revisiting symbiotic binaries with interferometry. I. The PIONIER archival collection
topic Solar and Stellar Astrophysics
url https://arxiv.org/abs/2502.04089