Article

# NSVS 06507557: A low-mass double-lined eclipsing binary

Ege University, Science Faculty, Astronomy and Space Sciences Department, 35100 Bornova, İzmir, Turkey
(Impact Factor: 5.11). 01/2010; 401(2):1141 - 1150. DOI: 10.1111/j.1365-2966.2009.15703.x

ABSTRACT

In this paper, we present the results of a detailed spectroscopic and photometric analysis of the V= 13.4 mag low-mass eclipsing binary NSVS 06507557 with an orbital period of 0.515 d. We have obtained a series of mid-resolution spectra covering nearly the entire orbit of the system. In addition, we have obtained simultaneous VRI broad-band photometry using a small aperture telescope. From these spectroscopic and photometric data, we have derived the system's orbital parameters and we have determined the fundamental stellar parameters of the two components. Our results indicate that NSVS 06507557 consists of a K9 pre-main-sequence star and an M3 pre-main-sequence star. These have masses of 0.66 ± 0.09 M⊙ and 0.28 ± 0.05 M⊙ and radii of 0.60 ± 0.03 and 0.44 ± 0.02 R⊙, respectively, and are located at a distance of 111 ± 9 pc. The radius of the less massive secondary component is larger than that of a zero-age main-sequence (ZAMS) star having the same mass. While the radius of the primary component is in agreement with ZAMS, the secondary component appears to be larger by about 35 per cent with respect to its ZAMS counterpart. Night-to-night intrinsic light variations up to 0.2 mag have been observed. In addition, the H and Hβ lines and the forbidden line of [O i] are seen in emission. The Li i 6708 Å absorption line is seen in most of the spectra. These features are taken to be signs of the characteristics of classic T Tauri stars. The parameters we have derived are consistent with an age of about 20 Myr, according to stellar evolutionary models. The spectroscopic and photometric results are in agreement with those obtained using theoretical predictions.

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Available from: Cafer İbanoǧlu, Jul 28, 2015
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ABSTRACT: By compiling an up-to-date catalog for the binary and multiple stellar systems containing pulsating components, we present a statistics on such systems. Compared to the compilation by Soydugan et al.(2006a) of 25 $\delta$ Scuti-type oscillating Algol-type eclipsing binaries plus 197 candidates, and the collection of Cepheids in binaries by Szabados (2003a), the types of both pulsating variables and binaries are now extended. The numbers have increased to be 190+ for all kinds of oscillating eclipsing binaries and more than 370 pulsating binary/multiple stellar systems. The catalog is intended to be a collection of pulsating binary stars across the Hertzsprung-Russell diagram. The open questions, progress and prospects connecting pulsation and binarity are reviewed. The observational implication of binary systems with pulsating components, to stellar evolution theories is also addressed. In addition, a catalog consisting of 434 confirmed Algol-type eclipsing binaries (EA) is provided for reference.