The first heavy-metal hot subdwarf composite binary SB 744

0548654 - ASÚ 2022 RIV FR eng J - Journal Article
Németh, Péter - Vos, Joris - Molina, F. - Bastian, A.
The first heavy-metal hot subdwarf composite binary SB 744.
Astronomy & Astrophysics. Roč. 653, September (2021), č. článku A3. ISSN 0004-6361. E-ISSN 1432-0746
R&D Projects: GA ČR(CZ) GA18-20083S
Institutional support: RVO:67985815
Keywords : stars * abundances * atmospheres
OECD category: Astronomy (including astrophysics,space science)
Impact factor: 6.240, year: 2021
Method of publishing: Open access with time embargo
https://doi.org/10.1051/0004-6361/202141442

The long-period sdOB+G1V type spectroscopic binary SB 744 reveals strong lines of fluorine and lead in the optical spectrum of the sdOB star and subsolar metallicity in the G1V companion thanks to a radial velocity follow-up study. Using high-quality observations and Gaia astrometric data, we aim to measure the chemical composition and Galactic kinematics of the system to put it into context with known populations of hot subdwarfs. Such binary systems have great potential to provide insights into the late stages of binary evolution as well as into the mysterious formation of stripped-core helium-burning stars. We analyzed the optical spectra with homogeneous atmospheric models to derive the surface parameters of the binary members from a direct wavelength space decomposition. Then, we independently measured the atmospheric properties of the cool companion. The two independent methods achieved consistent results, which were amended with constraints from spectral energy distributions to provide a subdwarf mass.
Permanent Link: http://hdl.handle.net/11104/0324700