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Observations of the population of cold Jupiter planets ($r>$1 AU) show that nearly all of these planets orbit their host star on eccentric orbits. For planets up to a few Jupiter masses, eccentric orbits are thought to be the outcome of planet-planet scattering events taking place after gas dispersal. We simulate the growth of planets via pebble and gas accretion as well as the migration of multiple planetary embryos in their gas disc. We then follow the long-term dynamical evolution of our formed planetary system up to 100 Myr after gas disc dispersal. We investigate the importance of the initial number of protoplanetary embryos and different damping rates of eccentricity and inclination during the gas phase for the final configuration of our planetary systems. We constrain our model by comparing the final dynamical structure of our simulated planetary systems to that of observed exoplanet systems. Our results show that the initial number of planetary embryos has only a minor impact on the final orbital eccentricity distribution of the giant planets, as long as damping of eccentricity and inclination is efficient. If damping is inefficient (slow), systems with a larger initial number of embryos harbor larger average eccentricities. In addition, for slow damping rates, we observe that scattering events already during the gas disc phase are common and that the giant planets formed in these simulations match the observed giant planet eccentricity distribution best. These simulations also show that massive giant planets (above Jupiter mass) on eccentric orbits are less likely to host inner super-Earths as these get lost during the scattering phase, while systems with less massive giant planets on nearly circular orbits should harbor systems of inner super-Earths. Finally, our simulations predict that giant planets are on average not single, but live in multi-planet systems.
We run numerical simulations to study the accretion of gas and dust grains onto gas giant planets embedded into massive protoplanetary discs. The outcome is found to depend on the disc cooling rate, planet mass, grain size and irradiative feedback fr
Earth-sized planets were observed in close-in orbits around M dwarfs. While more and more planets are expected to be uncovered around M dwarfs, theories of their formation and dynamical evolution are still in their infancy. We investigate the giant i
The omnipresence of super-Earths suggests that they are able to be retained in natal disks around low-mass stars, whereas exoplanets mass distribution indicates that some cores have transformed into gas giants through runaway gas accretion at 1AU fro
In the standard model of core accretion, the formation of giant planets occurs by two main processes: first, a massive core is formed by the accretion of solid material; then, when this core exceeds a critical value (typically greater than 10 Earth m
Very little is known about magnetic fields of extrasolar planets and brown dwarfs. We use the energy flux scaling law presented by Christensen et al. (2009) to calculate the evolution of average magnetic fields in extrasolar planets and brown dwarfs