Astronomy and Astrophysics – Astrophysics
Scientific paper
2005-08-12
Astronomy and Astrophysics
Astrophysics
6 pages, 3 figures. A&A (accepted)
Scientific paper
10.1051/0004-6361:20053048
We report the results of a deep photometric search for planets and brown dwarfs in the nearby young OB Upper Scorpius association. We obtained optical (I) and near-infrared (JKs) images around nine very low-mass stars and brown dwarf member candidates of the association, covering a total area of 113 arcmin^2. Using a point spread function subtraction technique, we have searched for planetary-mass companions (0.002 Msol < M < 0.013 Msol) at separations as close as 3 arcsec from the targets. We have not found any brown dwarfs more massive than 0.030 Msol at projected distances larger than 70AU, or planets more massive than 0.007 Msol at projected distances larger than 600AU. We set an upper limit of 20% (confidence level 68.3%) to the fraction of very low-mass stars and massive brown dwarfs with planetary mass companions (M > 0.007 Msol) at physical distances larger than 600AU. From the I, I-J colour-magnitude diagrams and follow-up Ks-band photometry, we identify four very red objects (I-J > 2.5) in the area of the survey. According to their positions in the diagram, below the expected theoretical sequence of the cluster, three are probable late M-dwarfs in the field. The faintest and reddest object (J-Ks = 2.39 +/- 0.06) may be either a field intermediate L-dwarf with anomalously red J-Ks colour at a distance of approx. 135pc, an extremely red distant galaxy, or a reddened planetary-mass object in the Upper Scorpius association.
Acosta-Pulido Jose
Bejar Víctor J. S.
Caballero Jose Antonio
Costado M. T.
Manchado Arturo
No associations
LandOfFree
A search for planetary-mass objects and brown dwarfs in the Upper Scorpius association does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with A search for planetary-mass objects and brown dwarfs in the Upper Scorpius association, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A search for planetary-mass objects and brown dwarfs in the Upper Scorpius association will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-37832