TAPIR Seminar

In person: 370 Cahill. To Join via Zoom: 868 5298 8404

ABSTRACT: Asteroseismology -- the analysis and interpretation of stellar oscillations -- remains the only means by which we may directly inspect the properties of stellar interiors. I will describe new theoretical developments regarding the interpretation of asteroseismic rotational signatures in a particular class of variable stars -- red-giant solar-like oscillators (ξ Hya stars). While waves in most variable stars propagate in a single mode cavity, I formulate a description of multicavity oscillations in these red giants by way of a physical analogy where they behave as "acoustic molecular orbitals". I describe two recent applications of this formalism, yielding 1. detection of engulfment signatures in evolved red giants, and 2. direct constraints on the misalignment angle between the rotational axis of the core and of the envelope, in the central star of a spin-orbit-misaligned planetary system.