2024/03/05 by Ritika Sethi, David V. Martin, Sethi, Ritika +1 · 3 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics of Galaxies (astro-ph.GA) #FOS: Physical sciences #History and Developments in Astronomy #Solar and Stellar Astrophysics (astro-ph.SR) #Stellar, planetary, and galactic studies
paper · pdf · doi:10.48550/arxiv.2403.03065
openalex publication_date 2024/03/05 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
Stellar binaries are ubiquitous in the galaxy and a laboratory for astrophysical effects. We use TESS to study photometric modulations in the 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 detect modulations on 81 eclipsing binaries. We catalog the rotation rates of the primary star in 69 binaries and discover 17 ellipsoidal variables. In a large portion (at least ∼ 51%) of our sample, we detect photometric modulations consistent with two over-densities of spots on the primary star that are roughly 180∘ apart. We show that 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.