The TWA 3 Young Triple System: Orbits, Disks, Evolution

Journal Article · Tue Aug 01 04:00:00 EDT 2017 · Astrophysical Journal

DOI:https://doi.org/10.3847/1538-4357/AA7C60· OSTI ID:22663303

Kellogg, Kendra ^[1]; Prato, L.; Avilez, I.; Wasserman, L. H.; Levine, S. E.; Bosh, A. S. ^[2]; Torres, Guillermo ^[3]; Schaefer, G. H. ^[4]; Ruíz-Rodríguez, D. ^[5]; Bonanos, Alceste Z. ^[6]; Guenther, E. W. ^[7]; Neuhäuser, R. ^[8]; Morzinski, Katie M.; Close, Laird; Hinz, Phil; Males, Jared R. ^[9]; Bailey, Vanessa ^[10]

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1. Department of Physics and Astronomy, The University of Western Ontario, London, ON N6A 3K7 (Canada)
2. Lowell Observatory, 1400 West Mars Hill Road, Flagstaff, AZ 86001 (United States)
3. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)
4. The CHARA Array of Georgia State University, Mount Wilson Observatory, Mount Wilson, CA 91023 (United States)
5. Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT 2611 (Australia)
6. IAASARS, National Observatory of Athens, 15236 Penteli (Greece)
7. Thüringer Landessternwarte Tautenburg, D-07778 Tautenburg (Germany)
8. Astrophysikalisches Institut und Universitäts-Sternwarte, FSU Jena, Schillergäßchen 2-3, D-07745 Jena (Germany)
9. Steward Observatory, University of Arizona, 933 N. Cherry Ave, Tucson, AZ 85721 (United States)
10. Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics, Stanford University, Stanford, CA, 94305 (United States)

We have characterized the spectroscopic orbit of the TWA 3A binary and provide preliminary families of probable solutions for the TWA 3A visual orbit, as well as for the wide TWA 3A–B orbit. TWA 3 is a hierarchical triple located at 34 pc in the ∼10 Myr old TW Hya association. The wide component separation is 1.″55; the close pair was first identified as a possible binary almost 20 years ago. We initially identified the 35-day period orbital solution using high-resolution infrared spectroscopy that angularly resolved the A and B components. We then refined the preliminary orbit by combining the infrared data with a reanalysis of our high-resolution optical spectroscopy. The orbital period from the combined spectroscopic solution is ∼35 days, the eccentricity is ∼0.63, and the mass ratio is ∼0.84; although this high mass ratio would suggest that optical spectroscopy alone should be sufficient to identify the orbital solution, the presence of the tertiary B component likely introduced confusion in the blended optical spectra. Using millimeter imaging from the literature, we also estimate the inclinations of the stellar orbital planes with respect to the TWA 3A circumbinary disk inclination and find that all three planes are likely misaligned by at least ∼30°. The TWA 3A spectroscopic binary components have spectral types of M4.0 and M4.5; TWA 3B is an M3. We speculate that the system formed as a triple, is bound, and that its properties were shaped by dynamical interactions between the inclined orbits and disk.

• OSTI ID: 22663303
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 844; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ABSORPTION SPECTROSCOPY
BINARY STARS
COMPUTERIZED SIMULATION
INCLINATION
INFRARED SPECTRA
INTERACTIONS
MASS
ORBITS
RESOLUTION
STAR EVOLUTION
STARS