Giant planet migration during the disc dispersal phase. (arXiv:2101.01179v1 [astro-ph.EP])
<a href="http://arxiv.org/find/astro-ph/1/au:+Monsch_K/0/1/0/all/0/1">Kristina Monsch</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Picogna_G/0/1/0/all/0/1">Giovanni Picogna</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Ercolano_B/0/1/0/all/0/1">Barbara Ercolano</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Kley_W/0/1/0/all/0/1">Wilhelm Kley</a>
Transition discs are expected to be a natural outcome of the interplay
between photoevaporation (PE) and giant planet formation. Massive planets
reduce the inflow of material from the outer to the inner disc, therefore
triggering an earlier onset of disc dispersal due to PE through a process known
as Planet-Induced PhotoEvaporation (PIPE). In this case, a cavity is formed as
material inside the planetary orbit is removed by PE, leaving only the outer
disc to drive the migration of the giant planet. We investigate the impact of
PE on giant planet migration and focus specifically on the case of transition
discs with an evacuated cavity inside the planet location. This is important
for determining under what circumstances PE is efficient at halting the
migration of giant planets, thus affecting the final orbital distribution of a
population of planets. For this purpose, we use 2D FARGO simulations to model
the migration of giant planets in a range of primordial and transition discs
subject to PE. The results are then compared to the standard prescriptions used
to calculate the migration tracks of planets in 1D planet population synthesis
models. The FARGO simulations show that once the disc inside the planet
location is depleted of gas, planet migration ceases. This contradicts the
results obtained by the impulse approximation, which predicts the accelerated
inward migration of planets in discs that have been cleared inside the
planetary orbit. These results suggest that the impulse approximation may not
be suitable for planets embedded in transition discs. A better approximation
that could be used in 1D models would involve halting planet migration once the
material inside the planetary orbit is depleted of gas and the surface density
at the 3:2 mean motion resonance location in the outer disc reaches a threshold
value of $0.01,mathrm{g,cm^{-2}}$.
Transition discs are expected to be a natural outcome of the interplay
between photoevaporation (PE) and giant planet formation. Massive planets
reduce the inflow of material from the outer to the inner disc, therefore
triggering an earlier onset of disc dispersal due to PE through a process known
as Planet-Induced PhotoEvaporation (PIPE). In this case, a cavity is formed as
material inside the planetary orbit is removed by PE, leaving only the outer
disc to drive the migration of the giant planet. We investigate the impact of
PE on giant planet migration and focus specifically on the case of transition
discs with an evacuated cavity inside the planet location. This is important
for determining under what circumstances PE is efficient at halting the
migration of giant planets, thus affecting the final orbital distribution of a
population of planets. For this purpose, we use 2D FARGO simulations to model
the migration of giant planets in a range of primordial and transition discs
subject to PE. The results are then compared to the standard prescriptions used
to calculate the migration tracks of planets in 1D planet population synthesis
models. The FARGO simulations show that once the disc inside the planet
location is depleted of gas, planet migration ceases. This contradicts the
results obtained by the impulse approximation, which predicts the accelerated
inward migration of planets in discs that have been cleared inside the
planetary orbit. These results suggest that the impulse approximation may not
be suitable for planets embedded in transition discs. A better approximation
that could be used in 1D models would involve halting planet migration once the
material inside the planetary orbit is depleted of gas and the surface density
at the 3:2 mean motion resonance location in the outer disc reaches a threshold
value of $0.01,mathrm{g,cm^{-2}}$.
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