Published January 1, 2020 | Version v1
Journal article

Irregular Dust Features around Intermediate-mass Young Stars with GPI: Signs of Youth or Misaligned Disks?

  • 1. Astrophysics Group, University of Exeter, Stocker Road, Exeter, EX4 4QL (United Kingdom)
  • 2. Department of Astronomy, University of Michigan, West Hall, 1085 South University Avenue, Ann Arbor, MI 48109-1090 (United States)
  • 3. University of North Carolina Greensboro, Greensboro, NC, 27402 (United States)
  • 4. Center for Astrophysics | Harvard & Smithsonian, 60 Garden Street, Cambridge, MA 02138 (United States)
  • 5. Department of Terrestrial Magnetism, Carnegie Institution for Science, 5241 Broad Branch Road, NW, Washington, DC 20015 (United States)
  • 6. Boston University, Boston, MA (United States)
  • 7. Department of Physics & Astronomy, Rice University, 6100 Main Street, Houston, TX 77005 (United States)
  • 8. University of Nevada, Las Vegas, NV (United States)

Description

We are undertaking a large survey of over 30 disks using the Gemini Planet Imager (GPI) to see whether the observed dust structures match spectral energy distribution predictions and have any correlation with stellar properties. GPI can observe near-infrared light scattered from dust in circumstellar environments using high-resolution Polarimetric Differential Imaging with coronagraphy and adaptive optics. The data have been taken in the J and H bands over two years, with inner working angles of 0.″08 and 0.″11, respectively. Ahead of the release of the complete survey results, here we present five objects with extended and irregular dust structures within 2″ of the central star. These objects are FU Ori, MWC 789, HD 45677, Hen 3-365, and HD 139614. The observed structures are consistent with each object being a pre-main-sequence star with protoplanetary dust. The five objects' circumstellar environments could result from extreme youth and complex initial conditions, from asymmetric scattering patterns due to shadows cast by misaligned disks, or in some cases from interactions with companions. We see complex U ϕ structures in most objects that could indicate multiple scattering or result from the illumination of companions. Specific key findings include the first high-contrast observation of MWC 789 revealing a newly discovered companion candidate and arc, and two faint companion candidates around Hen 3-365. These two objects should be observed further to confirm whether the companion candidates are comoving. Further observations and modeling are required to determine the causes of the structures.

Availability note (English)

Available from http://dx.doi.org/10.3847/1538-4357/ab59e2

Additional details

Identifiers

Publishing Information

Journal Title
Astrophysical Journal
Journal Volume
888
Journal Issue
1
Journal Page Range
[21 p.]
ISSN
0004-637X
CODEN
ASJOAB

INIS

Country of Publication
United Kingdom
Country of Input or Organization
International Atomic Energy Agency (IAEA)
INIS RN
52064935
Subject category
S79: ASTROPHYSICS, COSMOLOGY AND ASTRONOMY;
Descriptors DEI
CORRELATIONS; COSMIC DUST; FORECASTING; INTERACTIONS; MAIN SEQUENCE STARS; MASS; MULTIPLE SCATTERING; PLANETS; PROTOPLANETS; RESOLUTION; SIMULATION; STAR EVOLUTION
Descriptors DEC
DUSTS; EVOLUTION; SCATTERING; STARS