Paper: astro-ph/0512632
Date: Thu, 29 Dec 2005 02:18:57 GMT (19kb)

Title: On the Relation Between Hot Jupiters & the Roche Limit

Authors: Eric B. Ford (UC Berkeley), Frederic A. Rasio (Northwestern)

Comments: 10 pages, 3 figures, to appear in ApJL
\\
Many of the known extrasolar planets are ``hot Jupiters,'' giant planets with
orbital periods of just a few days. We use the observed distribution of hot
Jupiters to constrain the location of its inner edge in the mass--period
diagram. If we assume a slope corresponding to the classical Roche limit, then
we find that the edge corresponds to a separation close to_twice_ the Roche
limit, as expected if the planets started on highly eccentric orbits that were
later circularized. In contrast, any migration scenario would predict an inner
edge right at the Roche limit, which applies to planets approaching on nearly
circular orbits. However, the current sample of hot Jupiters is not sufficient
to provide a precise constraint simultaneously on both the location and slope
of the inner edge.

\\ ( http://arXiv.org/abs/astro-ph/0512632 , 19kb)