event
Wednesday 29 Jun 2011: Planets: a minor detail or a key driver of proto-stellar disc evolution?
Dr. Sergei Nayakshin - University of Leicester
Physics, 4th floor 11:00-11:45
Last decade established that massive ~ 100 AU gas discs fragment into
clumps. These clumps were thought to contract into massive planets or
brown dwarfs. However, recent numerical simulations (by 5 independent
groups so far) show that these clumps migrate inwards rapidly.
Significantly, the clumps may migrate faster than they contract, thus
getting tidally disrupted before they make a collapsed object. These
developments stimulated a new hypothesis for formation of all types of
planets (Boley et al 2010, Nayakshin 2010).
We show that planets exchange not only angular momentum but also mass
with the disc. In particular, ~10 M_jupiter proto planets entering the
inner 0.1 AU may be tidally stripped of their gas envelopes, dumping
their gas into the inner disc. This results in a FU Ori like outburst,
and leaves behind solid cores of the disrupted proto-giants --
presumably the "hot Super-Earth" planets observed in abundance by the
Kepler mission.