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arXiv · 1012.3732

Young Stars in the Time Domain: A Cool Stars 16 Splinter Summary

Kevin R. Covey·Peter Plavchan·Fabienne Bastien·Ettore Flaccomio·Kevin Flaherty·Stephen Marsden·Maria Morales-Calderón·James Muzerolle·Neal J. Turner
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Abstract

Variability is a defining characteristic of young stellar systems, and optical variability has been heavily studied to select and characterize the photospheric properties of young stars. In recent years, multi-epoch observations sampling a wider range of wavelengths and time-scales have revealed a wealth of time-variable phenomena at work during the star formation process. This splinter session was convened to summarize recent progress in providing improved coverage and understanding of time-variable processes in young stars and circumstellar disks. We begin by summarizing results from several multi-epoch Spitzer campaigns, which have demonstrated that many young stellar objects evidence significant mid-IR variability. While some of these variations can be attributed to processes in the stellar photosphere, others appear to trace short time-scale changes in the circumstellar disk which can be successfully modeled with axisymmetric or non-axisymmetric structures. We also review recent studies probing variability at shorter wavelengths that provide evidence for high frequency pulsations associated with accretion outbursts, correlated optical/X-ray variability in Classical T Tauri stars, and magnetic reversals in young solar analogs.

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Kevin R. Covey, Peter Plavchan, Fabienne Bastien, Ettore Flaccomio, Kevin Flaherty, Stephen Marsden, Maria Morales-Calderón, James Muzerolle, Neal J. Turner. 2010-12-16. Young Stars in the Time Domain: A Cool Stars 16 Splinter Summary. https://arxiv.org/abs/1012.3732

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