The first study of 54 new eccentric eclipsing binaries in our Galaxy^⋆

¹ Astronomical Institute, Charles University, Faculty of Mathematics and Physics, 180 00 Praha 8, V Holešovičkách 2, Czech Republic
e-mail: zasche@sirrah.troja.mff.cuni.cz
² Private Observatory, Pohoří 71, 254 01 Jílové u Prahy, Czech Republic
³ BSObservatory, Modrá 587, 760 01 Zlín, Czech Republic
⁴ Institute of Physics, Czech Academy of Sciences, Na Slovance 1999/2, 182 21 Praha 8, Czech Republic
⁵ Variable Star and Exoplanet Section of the Czech Astronomical Society, Vsetínská 941/78, 757 01 Valašské Meziříčí, Czech Republic
⁶ Úpice Observatory, U Lipek 160, 542 32 Úpice, Czech Republic
⁷ Astronomical Society Hradec Králové, Zámeček 456/30, 500 08 Hradec Králové, Czech Republic
⁸ Astronomical Institute, The Czech Academy of Sciences, Fričova 298, 251 65 Ondřejov, Czech Republic
⁹ School of Physical Sciences, The Open University, Walton Hall, Milton Keynes MK6 7AA, UK
¹⁰ RAL Space, The Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0NL, UK
¹¹ Jeremiah Horrocks Institute, University of Central Lancashire, Preston PR1 2HE, UK
¹² Hvězdárna, Kolářovy sady 3348, 796 01 Prostějov, Czech Republic
¹³ Instituto de Astrofísica de Andalucía, PO Box 03004, 18080 Granada, Spain
¹⁴ Weierstr 30, 8630 Rueti, Switzerland

Received: 8 February 2018
Accepted: 28 May 2018

Abstract

We present an analysis of the apsidal motion and light curve parameters of 54 never-before-studied galactic Algol-type binaries. This is the first analysis of such a large sample of eccentric eclipsing binaries in our Galaxy, and has enabled us to identify several systems that are worthy of further study. Bringing together data from various databases and surveys, supplemented with new observations, we have been able to trace the long-term evolution of the eccentric orbit over durations extending back up to several decades. Our present study explores a rather different sample of stars to those presented in the previously published catalogue of eccentric eclipsing binaries, sampling to fainter magnitudes, covering later spectral types, sensitive to different orbital periods with more than 50% of our systems having periods longer than six days. The typical apsidal motion in the sample is rather slow (mostly of order of centuries long), although in some cases this is less than 50 yr. All of the systems, except one, have eccentricities less than 0.5, with an average value of 0.23. Several of the stars also show evidence for additional period variability. In particular we can identify three systems in the sample, HD 44093, V611 Pup, and HD 313631, which likely represent relativistic apsidal rotators.