Astron. Astrophys. Suppl. Ser. 144, 317-321

Contribution à l'étude des binaires des types F, G, K, M

VIII. HD 195850 et HD 201193, binaires spectroscopiques à raies doubles
Contribution to the study of F, G, K, M binaries. VIII. HD 195850 and HD 201193, double-lined spectroscopic binaries

J.M. Carquillat - N. Ginestet

Observatoire Midi-Pyrénées, Laboratoire d'astrophysique (UMR 5572), 14 avenue Édouard Belin, F-31400 Toulouse, France

Reçu le 21 février; accepté le 23 mars 2000

Abstract:

Radial-velocity observations of the double-lined spectroscopic binaries HD 195850 and HD 201193 have been carried out at the Observatoire de Haute-Provence with the CORAVEL instrument in order to determine their orbital elements. They are as follows $\bullet$ HD 195850: P = 37.94106 days; T = 2444872.24 HJD; $\omega = 111^\circ 5$; e = 0.185; K₁ = 34.15 km s^-1; K₂ = 44.72 km s^-1; V₀ = 0.75 Km s^-1; $a_1 \sin i = 17.51$ Gm; $a_2 \sin i = 22.93$ Gm; $M_1 \sin^3i = 1.04~M_\odot$; $M_2 \sin^3i = 0.79~M_\odot$. $\bullet$ HD 201193: P = 22.299540 days; T = 2448137.004 HJD; $\omega = 144^\circ 7$; e = 0.388; K₁ = 54.15 km s^-1; K₂ = 54.77 km s^-1; V₀ = - 13.01 km s^-1; $a_1 \sin i = 15.31$ Gm; $a_2 \sin i = 15.48$ Gm; $M_1 \sin^3i = 1.179~M_\odot$; $M_2 \sin^3i = 1.165~M_\odot$. For HD 195850, we propose a F5V + G2V model on the basis of both the Hipparcos-measured parallax and the $\Delta m_v$ value, 1.1 mag, deduced from the intensities of the correlation dips. HD 201193, for its part, is formed by two quasi-identical F6V stars. Strömgren photometric indices suggest the following physical parameters: M_v = 3.6; $T_{\rm eff} = 6200$ K; $\log g = 4.2$. Using Schaller et al. (1992) evolutionary tracks for stars of solar metallicity, we estimate $M = 1.25~M_\odot$ for the mass of each component. This system should be somewhat evolved above the ZAMS, and the possibility of eclipses is, a priori, not excluded; it is likely that the components rotate in synchronism with the orbital motion.

Key words: stars: individual: HD 195850; HD 201193 -- binaries: spectroscopic -- stars: fundamental parameters