English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Double-lined eclipsing binaries allow the direct determination of masses andradii, which are key to test stellar models. With the launch of the TESSmission, many well-known eclipsing binaries have been observed at higherphotometric precision, permitting the improvement of the absolute dimensionsdeterminations. Using TESS data and newly-obtained spectroscopic observations,we aim at determining the masses and radii of the eccentric eclipsing binarysystems V889 Aql and V402 Lac, together with their apsidal motion parameters.We modelled simultaneously radial velocity curves and times of eclipse for eachtarget to precisely determine the orbital parameters of the systems, which weused to analyse the light curves and then obtain their absolute dimensions. Wecompared the obtained values with those predicted by theoretical models. Wedetermined masses and radii of the components of both systems with relativeuncertainties lower than 2%. V889 Aql is composed of two stars with masses$2.17\pm0.02$ M$_{\odot}$ and $2.13\pm0.01$ M$_{\odot}$ and radii $1.87\pm0.04$R$_{\odot}$ and $1.85\pm0.04$ R$_{\odot}$. We found conclusive evidence of thepresence of a third body orbiting V889 Aql with a period of 67 years. Based onthe detected third light and the absence of signal in the spectra, we suggestthat this third body could in turn be a binary composed by two $\sim$1.4M$_{\odot}$ stars. V402 Lac is composed by two stars with masses $2.80\pm0.05$M$_{\odot}$ and $2.78\pm0.05$ M$_{\odot}$ and radii $2.38\pm0.03$ R$_{\odot}$and $2.36\pm0.03$ R$_{\odot}$. The times of minimum light are compatible withthe presence of a third body for this system too, although its period is notyet fully sampled. In both cases we have found a good agreement between theobserved apsidal motion rates and the model predictions.

Absolute dimensions and apsidal motion of the eclipsing binaries V889 Aql and V402 Lac