Low-mass eclipsing binaries in TESS and CRÉME

Magnetic fields in low-mass (<0.8 Mʘ) stars affect the fundamental stellar properties. In short-period, tidally locked binaries fast rotation of components strengthens the magnetic field through a form of a dynamo mechanism, enhances activity, and affects the observed radii and effective temperatures, which has been observed in low-mass detached eclipsing binaries (LMDEB) for decades. Several descriptions of this phenomenon have been proposed, but we lack good quality observational data and models of LMDEBs in order to validate or falsify them.
    We present high-precision light curves of several M- and K-type, active detached eclipsing binaries, recorded with 2-minute cadence by the Transiting Exoplanet Survey Satellite (TESS). Analysis of these curves, combined radial velocity (RV) data from literature and the CRÉME survey, allows to vastly improve the accuracy and precision of stellar parameters with respect to previous studies of these systems. Results for one previously unpublished DEB are also presented.