X-ray emission processes in stars

Abstract

A decade of X-ray stellar observations with Chandra and XMM-Newton has led to significant advances in our understanding of the physical processes at work in hot (magnetized) plasmas in stars and their immediate environment, providing new perspectives and challenges, and in turn the need for improved models. The wealth of high-quality stellar spectra has allowed us to investigate, in detail, the characteristics of the X-ray emission across the HR diagram. Progress has been made in addressing issues ranging from classical stellar activity in stars with solar-like dynamos (such as flares, activity cycles, spatial and thermal structuring of the X-ray emitting plasma, evolution of X-ray activity with age), to X-ray generating processes (e.g. accretion, jets, magnetically confined winds) that were poorly understood in the pre-Chandra/XMM-Newton era. I discuss the progress made in the study of high energy stellar physics and its impact in a wider astrophysical context, focusing on the role of spectral diagnostics now accessible.

6 pages, 3 figures, invited review published in Proceedings of the National Academy of Sciences (part of the special 'First decade of Chandra' issue)

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Cited by in corpus (13)

• Stellar Activity and Coronal Heating: an overview of recent results
• IRIS observations of short-term variability in moss associated with transient hot coronal loops
• Element abundances in X-ray emitting plasmas in stars
• Hunting for millimeter flares from magnetic reconnection in pre-main sequence spectroscopic binaries
• EMISSA -- Exploring Millimeter Indicators of Solar-Stellar Activity I. The Initial mm-cm Main Sequence Star Sample
• Unsupervised Machine Learning for the Classification of Astrophysical X-ray Sources
• X-ray signature of antistars in the Galaxy
• Coronal Abundances in an Active Region: Evolution and Underlying Chromospheric and Transition Region Properties
• A Geologically Robust Procedure For Observing Rocky Exoplanets to Ensure that Detection of Atmospheric Oxygen is an Earth-Like Biosignature
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• XMM-Newton and Canadian Galactic Plane Survey Observations of the Supernova Remnant G107.5-1.5