ALMA MEASUREMENTS OF CIRCUMSTELLAR MATERIAL IN THE GQ LUP SYSTEM

Journal Article · Fri Jan 20 04:00:00 EST 2017 · Astrophysical Journal

DOI:https://doi.org/10.3847/1538-4357/835/1/17· OSTI ID:22664008

MacGregor, Meredith A.; Wilner, David J.; Czekala, Ian; Andrews, Sean M.; Ricci, Luca ^[1]; Dai, Y. Sophia ^[2]; Herczeg, Gregory J. ^[3]; Kratter, Kaitlin M. ^[4]; Kraus, Adam L. ^[5]; Testi, Leonardo ^[6]

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1. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
2. Caltech/IPAC, 1200 E. California Boulevard, Pasadena, CA, 91125 (United States)
3. Kavli Institute for Astronomy and Astrophysics, Peking University, Yi He Yuan Lu 5, Haidian Qu, 100871 Beijing (China)
4. Department of Astronomy, University of Arizona, Tucson, AZ 85721 (United States)
5. Department of Astronomy, The University of Texas at Austin, Austin, TX 78712 (United States)
6. European Southern Observatory (ESO) Headquarters, Karl-Schwarzschild-Str. 2, D-85748 Garching bei Muenchen (Germany)

We present Atacama Large Millimeter/submillimeter Array observations of the GQ Lup system, a young Sun-like star with a substellar-mass companion in a wide-separation orbit. These observations of 870 μ m continuum and CO J = 3–2 line emission with beam size ∼0.″3 (∼45 au) resolve the disk of dust and gas surrounding the primary star, GQ Lup A, and provide deep limits on any circumplanetary disk surrounding the companion, GQ Lup b. The circumprimary dust disk is compact with an FWHM of 59 ± 12 au, while the gas has a larger extent with a characteristic radius of 46.5 ± 1.8 au. By forward-modeling the velocity field of the circumprimary disk based on the CO emission, we constrain the mass of GQ Lup A to be M {sub *} = (1.03 ± 0.05) ∗ ( d /156 pc) M {sub ⊙}, where d is a known distance, and determine that we view the disk at an inclination angle of 60.°5 ± 0.°5 and a position angle of 346° ± 1°. The 3 σ upper limit on the 870 μ m flux density of any circumplanetary disk associated with GQ Lup b of <0.15 mJy implies an upper limit on the dust disk mass of <0.04 M {sub ⊕} for standard assumptions about optically thin emission. We discuss proposed mechanisms for the formation of wide-separation substellar companions given the non-detection of circumplanetary disks around GQ Lup b and other similar systems.

• OSTI ID: 22664008
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 835; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
CARBON MONOXIDE
DETECTION
DISTANCE
DUSTS
EMISSION
FLUX DENSITY
INCLINATION
MASS
ORBITS
SIMULATION
STARS
SUN
VELOCITY