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Most young stellar objects in nearby star forming regions reside in binary and multiple systems. Although circumstellar disks in these configurations are less massive and evolve more rapidly than their single star disk counterparts, many nevertheless persist for millions of years and have been shown to host young planets. Disks around the stars in the closest resolved young binaries, with separations of a few to tens of AU, are truncated at outer radii of ~1/3 the binary semi-major axis. Component-resolved, high-resolution spectra of the He I 10830A line show evidence for accretion plus winds from the stars and disks, launched over a range of radii and betraying the inner disk structure and activity. I will present results from recent He I 10830A observations, complemented with high-angular resolution data from ALMA and other facilities, for several binary systems in the Taurus region.
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Spectroscopic properties of stars in young binaries: fundamental data for understanding binary formation and disk evolution
Abstract This contribution combines a relatively comprehensive review of the spectroscopic study of the individual component stars and their associated disks in young binary systems, outlines the need for more in-depth studies, and previews the results of a high-spectral and high-angular resolution survey of $$\sim$$ ∼ 100 young binaries located primarily in the Taurus and Ophiuchus star forming regions. Observed spectra, synthetic spectral analysis, and preliminary outcomes for 3 systems are presented, illustrating the power and potential of adaptive optics-fed, high-resolution, infrared spectroscopy for our understanding of the dynamical and physical properties of young binary stars and their circumstellar disks and environments, especially when combined with ancillary data from ALMA, K2, TESS, and other facilities. This new survey will deepen our understanding of disk evolution and planet formation in close binaries and, more broadly, will provide clues to disk dissipation processes in both singles and binaries.
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- Award ID(s):
- 2109179
- PAR ID:
- 10435774
- Date Published:
- Journal Name:
- The European Physical Journal Plus
- Volume:
- 138
- Issue:
- 3
- ISSN:
- 2190-5444
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1140/epjp/s13360-023-03854-0
