2008ApJ...682.1264K -
Astrophys. J., 682, 1264-1276 (2008/August-1)
Planet formation around stars of various masses: hot super-Earths.
KENNEDY G.M. and KENYON S.J.
Abstract (from CDS):
We consider trends resulting from two formation mechanisms for short-period super-Earths: planet-planet scattering and migration. We model scenarios where these planets originate near the snow line in ``cold-finger'' circumstellar disks. Low-mass planet-planet scattering excites planets to low-periastron orbits only for lower mass stars. With long circularization times, these planets reside on long-period eccentric orbits. Closer formation regions mean planets that reach short-period orbits by migration are most common around low-mass stars. Above ∼1 M☉, planets massive enough to migrate to close-in orbits before the gas disk dissipates are above the critical mass for gas giant formation. Thus, there is an upper stellar mass limit for short-period super-Earths that form by migration. If disk masses are distributed as a power law, planet frequency increases with metallicity because most disks have low masses. For disk masses distributed around a relatively high mass, planet frequency decreases with increasing metallicity. As icy planets migrate, they shepherd interior objects toward the star, which grow to ∼1 M⊕. In contrast to icy migrators, surviving shepherded planets are rocky. On reaching short-period orbits, planets are subject to evaporation processes. The closest planets may be reduced to rocky or icy cores. Low-mass stars have lower EUV luminosities, so the level of evaporation decreases with decreasing stellar mass.
Abstract Copyright:
∼
Journal keyword(s):
Stars: Planetary Systems: Formation - Stars: Planetary Systems: Protoplanetary Disks
Simbad objects:
3
Full paper
View the references in ADS
To bookmark this query, right click on this link: simbad:2008ApJ...682.1264K and select 'bookmark this link' or equivalent in the popup menu