Unbound or Distant Planetary Mass Population Detected by Gravitational Microlensing

Details Unbound or Distant Planetary Mass Population Detected by Gravitational Microlensing Unbound or Distant Planetary Mass Population Detected by Gravitational Microlensing

2011-05-18

arxiv.org/abs/1105.3544v1

Nature, Volume 473, Issue 7347, p. 349-352 (2011)

Astronomy and Astrophysics

Astrophysics

Earth and Planetary Astrophysics

46 pages, 14 figures, include Supplementary Information, published in Nature

Scientific paper

10.1038/nature10092

Since 1995, more than 500 exoplanets have been detected using different techniques, of which 11 were detected with gravitational microlensing. Most of these are gravitationally bound to their host stars. There is some evidence of free-floating planetary mass objects in young star-forming regions, but these objects are limited to massive objects of 3 to 15 Jupiter masses with large uncertainties in photometric mass estimates and their abundance. Here, we report the discovery of a population of unbound or distant Jupiter-mass objects, which are almost twice (1.8_{-0.8}^{+1.7}) as common as main-sequence stars, based on two years of gravitational microlensing survey observations toward the Galactic Bulge. These planetary-mass objects have no host stars that can be detected within about ten astronomical units by gravitational microlensing. However a comparison with constraints from direct imaging suggests that most of these planetary-mass objects are not bound to any host star. An abrupt change in the mass function at about a Jupiter mass favours the idea that their formation process is different from that of stars and brown dwarfs. They may have formed in proto-planetary disks and subsequently scattered into unbound or very distant orbits.

Affiliated with

Also associated with

No associations

Rating

Unbound or Distant Planetary Mass Population Detected by Gravitational Microlensing 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 Unbound or Distant Planetary Mass Population Detected by Gravitational Microlensing, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Unbound or Distant Planetary Mass Population Detected by Gravitational Microlensing will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-53477