相关论文: Formation, Survival, and Detectability of Planets …

We have conducted an angular differential imaging survey with NIRC2 at Keck in search of close-in substellar companions to a sample of seven systems with confirmed planetary-mass companions (PMCs) on wide orbits (>50 AU). These…

We suggest that Jovian planets will survive the late stages of stellar evolution, and that white dwarfs will retain planetary systems in wide orbits (>5AU). Utilising evolutionary models for Jovian planets, we show that infra-red imaging…

We discuss the detectability of gravitationally bounded pairs of gas-giant planets (which we call "binary planets") in extrasolar planetary systems that are formed through orbital instability followed by planet-planet dynamical tides during…

Context: We studied numerically the formation of giant planet (GP) and brown dwarf (BD) embryos in gravitationally unstable protostellar disks and compared our findings with directly-imaged, wide-orbit (>= 50 AU) companions known to-date.…

In the nucleated instability picture of gas giant formation, the final stage is the rapid accretion of a massive gas envelope by a solid core, bringing about a tenfold or more increase in mass. This tends to trigger the scattering of any…

We present a statistical study of the post-formation migration of giant planets in a range of initial disk conditions. For given initial conditions we model the evolution of giant planet orbits under the influence of disk, stellar, and mass…

To date, two planetary systems have been discovered with close-in, terrestrial-mass planets (< 5-10 Earth masses). Many more such discoveries are anticipated in the coming years with radial velocity and transit searches. Here we investigate…

We have investigated i) the formation of gravitationally bounded pairs of gas-giant planets (which we call "binary planets") from capturing each other through planet-planet dynamical tide during their close encounters and ii) the following…

The discovery of planets around massive stars is important for understanding how planet formation and evolution is conditioned by different stellar environments. However, current planetary search surveys have failed to detect planets around…

Giant planets acquire gas, ices and rocks during the early formation stages of planetary systems and thus inform us on the formation process itself. Proceeding from inside out, examining the connections between the deep interiors and the…

Modeling the formation of cold giant planets around M dwarfs is difficult because their disks may not contain enough solids to form massive cores and because forming giants are expected to migrate inward through disk interactions. It is…

We present preliminary results from our spectroscopic search for planets within 1 AU of metal-poor field dwarfs using NASA time with HIRES on Keck I. The core accretion model of gas giant planet formation is sensitive to the metallicity of…

The orbital distributions of currently observed extrasolar giant planets allow marginally stable orbits for hypothetical, terrestrial planets. In this paper, we propose that many of these systems may not have additional planets on these…

Over 50 circumbinary exoplanets have been discovered in recent years, with several of them being gas giants on wide orbits ($>10$AU). The aim of this work is to investigate whether these planets can form through circumbinary disc…

Previous work concerning planet formation around low-mass stars has often been limited to large planets and individual systems. As current surveys routinely detect planets down to terrestrial size in these systems, a more holistic approach…

Understanding the formation and dynamical evolution of habitable planets in extrasolar planetary systems is a challenging task. In this respect, systems with multiple giant planets and/or multiple stars present special complications. The…

Binary systems are very common among field stars. While this relatively small number of planets in binaries is probably partly due to strong observational biases, there is, however, statistical evidence that planets are indeed less frequent…

As astronomers, we are living an exciting time for what concerns the search for other worlds. Recent discoveries have already deeply impacted our vision of planetary formation and architectures. Future bio-signature discoveries will…

Asteroid material is detected in white dwarfs (WDs) as atmospheric pollution by metals, in the form of gas/dust discs, or in photometric transits. Within the current paradigm, minor bodies need to be scattered, most likely by planets, into…

We simulate the formation of planetary systems around Alpha Centauri B. The N-body accretionary evolution of a 1/r disk populated with 400-900 lunar-mass protoplanets is followed for 200 Myr. All simulations lead to the formation of…