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arXiv · 2301.05617

A photometric study of NSVS 7453183: a probable quadruple system with long-term surface activity

L. Šmelcer·M. Wolf·H. Kučáková·P. Zasche·J. Kára·K. Hornoch·M. Zejda·R. F. Auer
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Abstract

The $VRC$ light curves were regularly measured for the eclipsing binary NSVS 7453183 as a part of our long-term observational project for studying of low-mass eclipsing binaries with a short orbital period and surface activity. The TESS light curve solution in Phoebe results to the detached configuration, where the temperature of primary component was adopted to $T_1$ = 4300 K according to the SED approximation. It gives us $T_2 =$ 4080 $\pm$ 100 K for the secondary component. The spectral type of the primary component was estimated to be K6 and the photometric mass ratio was derived $q = 0.86$. We confirm presence of the third body in this system, a stellar companion with a minimal mass 0.33 M$_{\rm Sun}$ orbiting the eclipsing pair with a short period about 425 days, and propose the next, fourth body with a longer orbiting period of about 12 years, probably a brown dwarf with the minimal mass of 50 M$_{\rm Jup}$. The hierarchical structure ((1+1)+1)+1 of this quadruple system is assumed. Characteristics and temporal variations of the dark region on the surface of the primary component were estimated. The average migration speed of about 10 deg/month was found during years 2020-2022.

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L. Šmelcer, M. Wolf, H. Kučáková, P. Zasche, J. Kára, K. Hornoch, M. Zejda, R. F. Auer. 2023-01-13. A photometric study of NSVS 7453183: a probable quadruple system with long-term surface activity. https://doi.org/10.1093/mnras%2Fstad053

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