Precision Analysis of Evolved Stars

Stephen Ridgway; Rachel Akeson; Ellyn Baines; Michelle Creech-Eakman; Tabetha Boyajian; Elvire De Beck; Andrea Dupree; Doug Gies; Kenneth Hinkle; Elizabeth Humphreys; Roberta Humphreys; Richard Joyce; Lynn Matthews; John Monnier; Ryan Norris; Rachael Roettenbacher; Letizia Stanghellini; Theo ten Brumellaar; Gerard van Belle; Wouter Vlemmings; J Craig Wheeler; Russell White; Lucy Ziurys

arXiv · 1903.05109

Precision Analysis of Evolved Stars

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Abstract

Evolved stars dominate galactic spectra, enrich the galactic medium, expand to change their planetary systems, eject winds of a complex nature, produce spectacular nebulae and illuminate them, and transfer material between binary companions. While doing this, they fill the HR diagram with diagnostic loops that write the story of late stellar evolution. Evolved stars sometimes release unfathomable amounts of energy in neutrinos, light, kinetic flow, and gravitational waves. During these late-life times, stars evolve complexly, with expansion, convection, mixing, pulsation, mass loss. Some processes have virtually no spatial symmetries, and are poorly addressed with low-resolution measurements and analysis. Even a "simple" question as how to model mass loss resists solution. However, new methods offer increasingly diagnostic tools. Astrometry reveals populations and groupings. Pulsations/oscillations support study of stellar interiors. Optical/radio interferometry enable 2-3d imagery of atmospheres and shells. Bright stars with rich molecular spectra and velocity fields are a ripe opportunity for imaging with high spatial and spectral resolution, giving insight into the physics and modeling of later stellar evolution.

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Stephen Ridgway, Rachel Akeson, Ellyn Baines, Michelle Creech-Eakman, Tabetha Boyajian, Elvire De Beck, Andrea Dupree, Doug Gies, Kenneth Hinkle, Elizabeth Humphreys, Roberta Humphreys, Richard Joyce, Lynn Matthews, John Monnier, Ryan Norris, Rachael Roettenbacher, Letizia Stanghellini, Theo ten Brumellaar, Gerard van Belle, Wouter Vlemmings, J Craig Wheeler, Russell White, Lucy Ziurys. 2019-03-12. Precision Analysis of Evolved Stars. https://arxiv.org/abs/1903.05109

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