CAOSP abstracts, Volume: 50, No.: 2, year: 2020

Author(s): Németh, P.
Journal: Contributions of the Astronomical Observatory Skalnaté Pleso, vol. 50, no. 2, p. 546-551.
Date: 3/2020
Title: Composite spectrum hot subdwarf binaries
Keyword(s): stars, hot subdwarfs, spectroscopy, composite spectra
Pages: 546 -- 551
DOI: https://doi.org/10.31577/caosp.2020.50.2.546
NASA ADS Abstract Service: 2020CoSka..50..546N
Citation:
License: This work is licensed under a Creative Commons Attribution 4.0 International License

Abstract: The formation of hot subdwarf stars (sdB) is closely related to binary evolution on the red giant branch. Observations show that hot subdwarfs are either in close binaries with low mass K-M type or white dwarf companions, or in wide binaries with more massive F-G type companions. A small fraction is most strikingly single. In close binaries the radiative interactions give rise to the reflection effect and produces a variable composite spectrum. More massive companions bear similar optical luminosities as sdB stars and therefore double-lined spectra are observed. To investigate such systems in detail and precision spectral decomposition/disentangling is needed. I describe our wavelength space disentangling method and bring examples why such an approach to composite spectra offers a potential to find the history of hot subdwarfs.