skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: TWO WIDE PLANETARY-MASS COMPANIONS TO SOLAR-TYPE STARS IN UPPER SCORPIUS

Journal Article · · Astrophysical Journal
 [1];  [2];  [3];  [4];  [5]
  1. Sydney Institute for Astronomy (SIfA), School of Physics, University of Sydney, NSW 2006 (Australia)
  2. Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States)
  3. National Astronomical Observatory of Japan, Subaru Telescope, Hilo, HI 96720 (United States)
  4. Dunlap Institute for Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto M5S 3H4, Ontario (Canada)
  5. Department of Astrophysics, California Institute of Technology, MC 105-24, Pasadena, CA 91125 (United States)

At wide separations, planetary-mass and brown dwarf companions to solar-type stars occupy a curious region of parameter space not obviously linked to binary star formation or solar system scale planet formation. These companions provide insight into the extreme case of companion formation (either binary or planetary), and due to their relative ease of observation when compared to close companions, they offer a useful template for our expectations of more typical planets. We present the results from an adaptive optics imaging survey for wide ({approx}50-500 AU) companions to solar-type stars in Upper Scorpius. We report one new discovery of a {approx}14 M{sub J} companion around GSC 06214-00210and confirm that the candidate planetary-mass companion 1RXS J160929.1-210524 detected by Lafreniere et al. is in fact comoving with its primary star. In our survey, these two detections correspond to {approx}4% of solar-type stars having companions in the 6-20 M{sub J} mass and {approx}200-500 AU separation range. This figure is higher than would be expected if brown dwarfs and planetary-mass companions were drawn from an extrapolation of the binary mass function. Finally, we discuss implications for the formation of these objects.

OSTI ID:
21567646
Journal Information:
Astrophysical Journal, Vol. 726, Issue 2; Other Information: DOI: 10.1088/0004-637X/726/2/113; ISSN 0004-637X
Country of Publication:
United States
Language:
English