An informal seminar series to highlight work from early career researchers from institutions around the world.
Ritika will join us remotely for this event. As always, you are welcome to join us in the fourth-floor Sterling conference room. For those who are unable to attend in person, we will also be hosting the meeting via Zoom.
Talk title: Tidal Synchronization and Stellar Activity on Low Mass Eclipsing Binaries with TESS
Abstract: Stellar binaries are ubiquitous in the galaxy and an excellent laboratory for understanding tidal evolution and synchronization. In this talk, I will discuss my recent work involving the study of photometric modulations in the TESS lightcurves of 162 unequal-mass eclipsing binaries from the EBLM (Eclipsing Binary Low Mass) survey, comprising F/G/K primaries and M-dwarf secondaries. We detected modulations on 81 eclipsing binaries and estimated their rotation rates. We also discovered ellipsoidal variations (tidally-driven distortions) in 17 of our binary systems. Using our rotation period measurements, we investigated the dependence of tides on orbital period, eccentricity, primary star parameters, and mass ratios. This allowed us to probe the transition regime of when tides are and are not significant in tight unequal mass binaries. Additionally, in a large portion (at least ~51%) of our sample, we detected photometric modulations consistent with two over-densities of spots on the primary star that are roughly 180° apart. These so-called active longitudes are preferentially at the sub- and anti-stellar points on the primary star. Physically, this means that the spots on the primary star preferentially face directly towards and away from the secondary star.
Organized by: Leon Trapman, Dan Rybarczyk, Nickolas Pingel, Melinda Soares-Furtado