Triple Eccentric Systems V0345 Lac, YY Sgr, and DR Vul
M. Wolf1,
P. Zasche1,
H. Kučáková1,2,3,4,
M. Mašek2,5,
K. Hoňková2,
J. Juryšek2,5,
A. Paschke2,6,
L. Šmelcer2,7 and
M. Zejda8
1Astronomical Institute, Faculty of Mathematics and Physics, Charles University, V Holešovičkách 2, CZ-180 00 Praha 8, Czech Republic,
e-mail: wolf@cesnet.cz
2Variable Star and Exoplanet Section, Czech Astronomical Society
3Institute of Physics, Faculty of Philosophy and Science, Silesian University in Opava, Bezručovo nám. 13, CZ-746 01 Opava, Czech Republic
4Astronomical Institute, Academy of Sciences, Fričova 298, CZ-251 65 Ondřejov, Czech Republic
5Institute of Physics, Czech Academy of Sciences, Na Slovance 1999/2, CZ-182 21 Praha 8, Czech Republic
6Weierstrasse 30, CH-8630 Rueti, Switzerland
7Observatory, Vsetínská 78, CZ-757 01 Valašské Meziříčí, Czech Republic
8Department of Theoretical Physics and Astrophysics, Masaryk University, Kotlářská 2, 611 37 Brno, Czech Republic
Received: August 28, 2018
ABSTRACT
We present more results of our long-term observational project to
analyze the variations of the orbital period for early-type eccentric
eclipsing binaries. About sixty new precise mid-eclipse times were
measured or derived for three eclipsing binaries, namely
V0345 Lac, YY Sgr, and DR Vul. Based on
current O-C diagrams, we found in all cases that beside the
typical apsidal motion the times of minima show additional cyclical
changes likely caused by a third body orbiting the eclipsing pair.
The new light curve solution of V0345 Lac results in a moderate
orbital eccentricity (e=0.26) of this binary. The periods of
apsidal motion are 1580 yr, 295 yr, and 36 yr,
respectively. The relativistic contributions to the total
apsidal-motion rate are small for all three eccentric binaries -
about 5-14%. The third-body orbital periods are relatively short:
24 yr, 19 yr and 66 yr, and the minimal masses of third bodies
are: 2.0 M☉, 0.8 M☉, and
7.2 M☉, respectively.
Key words:
binaries: eclipsing - Stars: individual: V0345 Lac, YY Sgr, and DR Vul - stars: fundamental
parameters