Astronomy and Astrophysics – Astrophysics
Scientific paper
2005-09-30
Mon.Not.Roy.Astron.Soc.364:961-970,2005
Astronomy and Astrophysics
Astrophysics
11 pages, 9 figures, using aas_macros.sty. MNRAS, accepted
Scientific paper
10.1111/j.1365-2966.2005.09644.x
We present a parameter study of the possibility of tidally triggered disk instability. Using a restricted N-body model which allows for a survey of an extended parameter space, we show that a passing dwarf star with a mass between 0.1 and 1 M_sun can probably induce gravitational instabilities in the pre-planetary solar disk for prograde passages with minimum separations below 80-170 AU for isothermal or adiabatic disks. Inclined and retrograde encounters lead to similar results but require slightly closer passages. Such encounter distances are quite likely in young moderately massive star clusters (Scally & Clarke 2001; Bonnell et al. 2001). The induced gravitational instabilities may lead to enhanced planetesimal formation in the outer regions of the protoplanetary disk, and could therefore be relevant for the existence of Uranus and Neptune, whose formation timescale of about 100 Myr (Wuchterl, Guillot & Lissauer 2000) is inconsistent with the disk lifetimes of about a few Myr according to observational data by Haisch, Lada & Lada (2001). The relatively small gas/solid ratio in Uranus and Neptune can be matched if the perturbing fly-by occurred after early gas depletion of the solar system, i.e. when the solar system was older than about 5 Myr. We also confirm earlier results by Heller (1993) that the observed 7 degree tilt of the solar equatorial plane relative to the ecliptic plane could be the consequence of such a close encounter.
Kroupa Pavel
Theis Christian
Thies Ingo
No associations
LandOfFree
Induced planet formation in stellar clusters - a parameter study of star-disk encounters 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 Induced planet formation in stellar clusters - a parameter study of star-disk encounters, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Induced planet formation in stellar clusters - a parameter study of star-disk encounters will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-310800