Related papers: Circumstellar Disk Evolution: Constraining Theorie…
Planetary systems are angular momentum reservoirs generated during star formation. This accretion process produces very powerful engines able to drive the optical jets and the molecular outflows. A fraction of the engine energy is released…
The study of the last stages of planet formation, also known as debris disks, is fundamental to place constrains on the formation of planetary sized bodies. Debris disks are composed of dust and occasionally small amounts of gas, both…
The chemical composition of stars that have orbiting planets provides important clues about the frequency, architecture, and composition of exoplanet systems. We explore the possibility that stars from different galactic populations that…
Stars form from the gravitational collapse of dense molecular cloud cores. In the protostellar phase, mass accretes from the core onto a protostar, likely through an accretion disk, and it is during this phase that the initial masses of…
We combine the results from several multiplicity surveys of pre-main-sequence stars located in four nearby star-forming regions with Spitzer data from three different Legacy Projects. This allows us to construct a sample of 349 targets,…
Debris disks are exoplanetary systems containing planets, minor bodies (such as asteroids and comets) and debris dust. Unseen planets are presumed to perturb the minor bodies into crossing orbits, generating small dust grains that are…
Circumstellar discs are the precursors of planetary systems and develop shortly after their host star has formed. In their early stages these discs are immersed in an environment rich in gas and neighbouring stars, which can be hostile for…
Global star formation is the key to understanding galaxy disk formation. This in turn depends on gravitational instability of disks and continuing gas accretion as well as minor merging. A key component is feedback from supernovae. Primary…
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…
The initial conditions, physics, and outcome of planet formation are now constrained by detailed observations of protoplanetary disks, laboratory experiments, and the discovery of thousands of extrasolar planetary systems. These…
As stellar compositions evolve over time in the Milky Way, so will the resulting planet populations. In order to place planet formation in the context of Galactic chemical evolution, we make use of a large ($N = 5\,325$) stellar sample…
The field of planet formation is in an exciting era, where recent observations of disks around low- to intermediate-mass stars made with state of the art interferometers and high-contrast optical and IR facilities have revealed a diversity…
Planet formation is generally described in terms of a system containing the host star and a protoplanetary disc, of which the internal properties (e.g. mass and metallicity) determine the properties of the resulting planetary system.…
I review observational studies of the large-scale star formation process in nearby galaxies. A wealth of new multi-wavelength data provide an unprecedented view on the interplay of the interstellar medium and (young) stellar populations on…
High-energy irradiation of the circumstellar material might impact the structure and the composition of a protoplanetary disk and hence the process of planet formation. In this paper, we present a study on the possible influence of the…
Young stars are surrounded by copious amounts of circumstellar material. Its composition, in particular its gas-to-dust ratio, is an important parameter. However, measuring this ratio is challenging, because gas mass estimates are often…
Self-gravitating protostellar discs are unstable to fragmentation if the gas can cool on a time scale that is short compared to the orbital period. We use a combination of hydrodynamic simulations and N-body orbit integrations to study the…
The advent of the Spitzer Space Telescope has revolutionized our understanding of the history of star formation and galaxy mass assembly in the Universe. The tremendous leap in sensitivity from previous mid-to-far IR missions has allowed…
Planets form and obtain their compositions in disks of gas and dust around young stars. The chemical compositions of these planet-forming disks regulate all aspects of planetary compositions from bulk elemental inventories to access to…
Observations indicate that the gaseous circumstellar disks around young stars vary significantly in size, ranging from tens to thousands of AU. Models of planet formation depend critically upon the properties of these primordial disks, yet…