Astronomy and Astrophysics – Astrophysics
Scientific paper
2004-12-15
Astrophys.J. 640 (2006) 1051-1062
Astronomy and Astrophysics
Astrophysics
Conforms to version accepted by ApJ. 13 pages formatted with emulateapj.cls
Scientific paper
10.1086/500161
Sun-like stars have stellar, brown dwarf and planetary companions. To help constrain their formation and migration scenarios, we analyse the close companions (orbital period < 5 years) of nearby Sun-like stars. By using the same sample to extract the relative numbers of stellar, brown dwarf and planetary companions, we verify the existence of a very dry brown dwarf desert and describe it quantitatively. With decreasing mass, the companion mass function drops by almost two orders of magnitude from 1 M_Sun stellar companions to the brown dwarf desert and then rises by more than an order of magnitude from brown dwarfs to Jupiter-mass planets. The slopes of the planetary and stellar companion mass functions are of opposite sign and are incompatible at the 3 sigma level, thus yielding a brown dwarf desert. The minimum number of companions per unit interval in log mass (the driest part of the desert) is at M = 31^{+25}_{-18} M_Jup. Approximately 16% of Sun-like stars have close (P < 5 years) companions more massive than Jupiter: 11% +- 3% are stellar, <1% are brown dwarf and 5% +- 2% are giant planets. The steep decline in the number of companions in the brown dwarf regime, compared to the initial mass function of individual stars and free-floating brown dwarfs, suggests either a different spectrum of gravitational fragmentation in the formation environment or post-formation migratory processes disinclined to leave brown dwarfs in close orbits.
Grether Daniel
Lineweaver Charles H.
No associations
LandOfFree
How Dry is the Brown Dwarf Desert?: Quantifying the Relative Number of Planets, Brown Dwarfs and Stellar Companions around Nearby Sun-like Stars 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 How Dry is the Brown Dwarf Desert?: Quantifying the Relative Number of Planets, Brown Dwarfs and Stellar Companions around Nearby Sun-like Stars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and How Dry is the Brown Dwarf Desert?: Quantifying the Relative Number of Planets, Brown Dwarfs and Stellar Companions around Nearby Sun-like Stars will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-91922