Stellar Physics with High-Resolution UV Spectropolarimetry

Julien Morin; Jean-Claude Bouret; Coralie Neiner; Conny Aerts; Stefano Bagnulo; Claude Catala; Corinne Charbonnel; Chris Evans; Luca Fossati; Miriam Garcia; Ana I Gómez de Castro; Artemio Herrero; Gaitee Hussain; Lex Kaper; Oleg Kochukhov; Renada Konstantinova-Antova; Alex de Koter; Michaela Kraus; Jiří\K{r}tička; Agnes Lèbre; Theresa Lueftinger; Georges Meynet; Pascal Petit; Steve Shore; Sami Solanki; Beate Stelzer; Antoine Strugarek; Aline Vidotto; Jorick S Vink

arXiv · 1908.01545

Stellar Physics with High-Resolution UV Spectropolarimetry

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Abstract

Current burning issues in stellar physics, for both hot and cool stars, concern their magnetism. In hot stars, stable magnetic fields of fossil origin impact their stellar structure and circumstellar environment, with a likely major role in stellar evolution. However, this role is complex and thus poorly understood as of today. It needs to be quantified with high-resolution UV spectropolarimetric measurements. In cool stars, UV spectropolarimetry would provide access to the structure and magnetic field of the very dynamic upper stellar atmosphere, providing key data for new progress to be made on the role of magnetic fields in heating the upper atmospheres, launching stellar winds, and more generally in the interaction of cool stars with their environment (circumstellar disk, planets) along their whole evolution. UV spectropolarimetry is proposed on missions of various sizes and scopes, from POLLUX on the 15-m telescope LUVOIR to the Arago M-size mission dedicated to UV spectropolarimetry.

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Julien Morin, Jean-Claude Bouret, Coralie Neiner, Conny Aerts, Stefano Bagnulo, Claude Catala, Corinne Charbonnel, Chris Evans, Luca Fossati, Miriam Garcia, Ana I Gómez de Castro, Artemio Herrero, Gaitee Hussain, Lex Kaper, Oleg Kochukhov, Renada Konstantinova-Antova, Alex de Koter, Michaela Kraus, Jiří\K{r}tička, Agnes Lèbre, Theresa Lueftinger, Georges Meynet, Pascal Petit, Steve Shore, Sami Solanki, Beate Stelzer, Antoine Strugarek, Aline Vidotto, Jorick S Vink. 2019-08-05. Stellar Physics with High-Resolution UV Spectropolarimetry. https://arxiv.org/abs/1908.01545

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