A Search for Companions to Nearby Brown Dwarfs: the Binary DENIS-P J1228.2-1547

Eduardo L. Martín, Wolfgang Brandner, Gibor Basri

1999, Science 283, 1718

Abstract

Hubble Space Telescope near infrared camera and multiobject spectrometer (NICMOS) imaging observations of two nearby brown dwarfs, DENIS-P J1228.2-1547 and Kelu 1, show that the DENIS object is resolved into two components of nearly equal brightness with a projected separation of 0.275 arcsec (5 astronomical units for a distance of 18 parsecs). The binary system can provide the first dynamical measurement if the masses of two brown dwarfs in only a few years. Upper limits to the mass of any unseen companion in Kelu 1 yield a planet of 7 Jupiter masses and age 0.5 Gyr, that would have been detected at a separation larger than 4 astronomical units. This example demonstrates that giant planets could be detected by direct imaging if they exist in Jupiter-like orbits around nearby young brown dwarfs.

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