Detection of seven 2+2 doubly eclipsing quadruple systems

¹ Charles University, Faculty of Mathematics and Physics, Astronomical Institute, V Holešovičkách 2, 180 00 Praha 8, Czech Republic
e-mail: zasche@sirrah.troja.mff.cuni.cz
² Hvězdárna Jaroslava Trnky ve Slaném, Nosačická 1713, Slaný 1 274 01, Czech Republic
³ Variable Star and Exoplanet Section, Czech Astronomical Society, Fričova 298, 251 65 Ondřejov, Czech Republic
⁴ FZU – Institute of Physics of the Czech Academy of Sciences, Na Slovance 1999/2, 182 00 Praha, Czech Republic
⁵ Astronomical Institute, Academy of Sciences, Fričova 298, 251 65 Ondřejov, Czech Republic
⁶ Research Centre for Theoretical Physics and Astrophysics, Institute of Physics, Silesian University in Opava, Bezručovo nám. 13, 746 01 Opava, Czech Republic

Received: 9 May 2023
Accepted: 26 May 2023

Abstract

In this work, we study a heterogeneous group of seven stellar systems for the first time. Despite their different distances or spectral types, all of them belong to a very rare group of quadruple systems of 2+2 architecture, where both of the inner pairs harbor eclipsing binaries. These systems are: ASASSN-V J102911.57−522413.6 (inner periods 0.57272, and 3.79027 days), V1037 Her (0.78758 and 5.80348 days), WISE J181904.2+241243 (0.36713 and 0.41942 days), V2894 Cyg (2.57434 and 1.30579 days), NSVS 5725040 (1.79368 and 0.76794 days), WISE J210230.8+610816 (1.84324 and 0.57159 days), and ZTF J220518.78+592642.1 (2.79572 and 3.34615 days). Their outer mutual periods are: 9.3, 25.4, 18.7, 27.5, 2.6, 2.2, and 14.0 yr, respectively. These outer periodicities were derived using longer time span of photometric observations of these systems and analysing their period changes of both inner pairs via ETVs (eclipse-timing variations). Most of these studied systems are detached, as evidenced by the proper modelling of their light curves. A few of them show significant eccentric orbits with apsidal motion (e.g., V2894 Cyg, and NSVS 5725040). Further spectroscopic follow-up observations would offer a better characterization of the component star’s parameters (for e.g., NSVS 5725040), as well as a potential interferometric detection of the systems as real doubles on their mutual orbits (for e.g., V1037 Her). A rather interesting excess of systems close to a 3:2 mean motion resonance is seen only for early spectral-type stars with higher temperatures.