2005/03/31 by Slavek M. Rucinski, S. M. Ruciński, Wojtek Pych +10
Mathematics · Physics and Astronomy · #Astro and Planetary Science #Astrophysics #Astrophysics and Star Formation Studies #Binary number #Binary star #Binary system #Contact binary #Light curve #Mass ratio #Mathematics #Orbit (dynamics) #Physics #Radial velocity #Stars #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1086/431226
published as Astron.J.130:767-775,2005; Erratum-ibid.134:445,2007 · Accepted by AJ, August 2005; 5 figures
arxiv created 2005/04/21 · openalex publication_date 2005/07/19 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/08
Radial velocity measurements and sine-curve fits to orbital velocity variations are presented for the ninth set of 10 close binary systems: V395 And, HS Aqr, V449 Aur, FP Boo, SW Lac, KS Peg, IW Per, V592 Per, TU UMi, and FO Vir. The first three are very close, possibly detached, early-type binaries, and all three require further investigation. Particularly interesting is V395 And, whose spectral type is as early as B7/8 for a 0.685 day orbit binary. KS Peg and IW Per are single-line binaries, with the former probably hosting a very low mass star. We have detected a low-mass secondary in an important semidetached system, FO Vir, at q = 0.125 ± 0.005. The contact binary FP Boo is also a very small mass ratio system, q = 0.106 ± 0.005. The other contact binaries in this group are V592 Per, TU UMi, and the well-known SW Lac. V592 Per and TU UMi have bright tertiary companions; for these binaries, and for V395 And, we used a novel technique of arranging the broadening functions into a two-dimensional image in phase. The case of TU UMi turned out to be intractable even using this approach, and we have not been able to derive a firm radial velocity orbit for this binary. Three systems of this group were observed spectroscopically before: HS Aqr, SW Lac, and KS Peg.