A&A 614, A60 (2018) https://doi.org/10.1051/0004-6361/201732376 Astronomy & © ESO 2018 Astrophysics Fundamental parameters of massive stars in multiple systems: The cases of HD 17505A and HD 206267A? F. Raucq1, G. Rauw1, L. Mahy1,2,??, and S. Simón-Díaz3,4 1 Space sciences, Technologies and Astrophysics Research (STAR) Institute, Université de Liège, Allée du 6 Août 19c, Bât. B5c, 4000 Liège, Belgium e-mail:
[email protected] 2 Instituut voor Sterrenkunde, KU Leuven, Celestijnenlaan 200D, Bus 2401, 3001 Leuven, Belgium 3 Instituto de Astrofísica de Canarias, 38200 La Laguna, Tenerife, Spain 4 Departamento de Astrofísica, Universidad de La Laguna, 38205 La Laguna, Tenerife, Spain Received 28 November 2017 / Accepted 23 February 2018 ABSTRACT Context. Many massive stars are part of binary or higher multiplicity systems. The present work focusses on two higher multiplicity systems: HD 17505A and HD 206267A. Aims. Determining the fundamental parameters of the components of the inner binary of these systems is mandatory to quantify the impact of binary or triple interactions on their evolution. Methods. We analysed high-resolution optical spectra to determine new orbital solutions of the inner binary systems. After subtracting the spectrum of the tertiary component, a spectral disentangling code was applied to reconstruct the individual spectra of the primary and secondary. We then analysed these spectra with the non-LTE model atmosphere code CMFGEN to establish the stellar parameters and the CNO abundances of these stars. Results. The inner binaries of these systems have eccentric orbits with e ∼ 0:13 despite their relatively short orbital periods of 8.6 and 3.7 days for HD 17505Aa and HD 206267Aa, respectively.