Léa Planquart (Chalmers University of Technology): Shaping bipolar nebula of dusty evolved stars: a search for binaries

Thursday 4 Dec 2025, 14:00 → 15:00 Europe/Stockholm

101190

Title: Shaping bipolar nebula of dusty evolved stars: a search for binaries
Speaker: Léa Planquart
Affiliation: Chalmers University of Technology
Room: Å101190
Time: 14:00-15:00

Abstract:

About half of the stars with a low to intermediate initial mass are born with a companion. However, when these stars evolve to their asymptotic giant branch (AGB), the fraction of detected binaries is scarce. The cause of this disparity is observational: the dusty, variable nature of the close circumstellar environment of the AGB star challenges traditional binary-detection techniques. Constraining the interaction mechanisms of AGB binaries is, nevertheless, crucial to understanding how they shape their wind morphology and the formation of the progeny.
In this talk, I will present a multi-instrumental study of the AGB binary V Hydrae. I will highlight how combining the resolving power of complementary observational techniques (including spectroscopic monitoring and infrared interferometry) can efficiently disentangle orbital from intrinsic variability, enabling us to detect a stellar companion through its impact on the gas and dust distribution at different scales.
I will then conclude by addressing some observational constraints regarding the AGB pulsation and the origin of the period obscuration event.