Related papers: Rapid disappearance of a warm, dusty circumstellar…
We reconsider the commonly held assumption that warm debris disks are tracers of terrestrial planet formation. The high occurrence rate inferred for Earth-mass planets around mature solar-type stars based on exoplanet surveys (roughly 20%)…
Over the past 10 years abundant evidence has emerged that many (if not all) stars are born with circumstellar disks. Understanding the evolution of post-accretion disks can provide strong constraints on theories of planet formation and…
Discs of gas and dust around Myr-old stars are a by-product of the star formation process and provide the raw material to form planets. Hence, their evolution and dispersal directly impact what type of planets can form and affect the final…
We discuss the properties of several circumstellar debris disk systems imaged with the Hubble Space Telescope's Near Infrared Camera and Multi-Object Spectrometer in a survey of young stars with known far-IR excesses. These dusty disks…
Extensive photometric stellar surveys show that many main sequence stars show emission at infrared and longer wavelengths that is in excess of the stellar photosphere; this emission is thought to arise from circumstellar dust. The presence…
Circumstellar disks have long been regarded as windows into planetary systems. The advent of high sensitivity, high resolution imaging in the submillimetre where both the solid and gas components of disks can be detected opens up new…
A detailed understanding of the physics of star and planet formation requires study of individual objects as well as statistical assessment of global properties and evolutionary trends. Observational investigations of circumstellar material…
Planet-forming circumstellar disks are a fundamental part of the star formation process. Since stars form in a hierarchical fashion in groups of up to hundreds or thousands, the UV radiation environment that these disks are exposed to can…
Stars and planets form, live, and evolve in unison. Throughout the life of a star, dusty circumstellar discs and stellar outflows influence the further evolution of both the star(s) and their orbiting planet(s). Planet-forming discs, winds…
Newly formed stars are often observed to possess circumstellar disks, from which mass continues to be accreted onto the star and fed into outflowing jets, and which eventually may evolve into dusty debris disks and planetary systems. Recent…
Thousands of confirmed and candidate exoplanets have been identified in recent years. Consequently, theoretical research on the formation and dynamical evolution of planetary systems has seen a boost, and the processes of planet-planet…
The formation of planets is one of the major unsolved problems in modern astrophysics. Planets are believed to form out of the material in circumstellar disks known to exist around young stars, and which are a by-product of the star…
It has been suggested that circumstellar disks evolve from dense, actively accreting structures to low-mass, replenished remnants. During this transition, grains may assemble into planetesimals, or the disk may be cleared by newborn…
Observations of circumstellar disks around stars as a function of stellar properties such as mass, metallicity, multiplicity, and age, provide constraints on theories concerning the formation and evolution of planetary systems. Utilizing…
The evolution of circumstellar discs is influenced by their surroundings. The relevant processes include external photoevaporation due to nearby stars, and dynamical truncations. The impact of these processes on disc populations depends on…
Circumstellar disks are an integral part of the star formation process and the sites where planets are formed. Understanding the physical processes that drive their evolution, as disks evolve from optically thick to optically thin, is…
A question central to understanding the origin of our solar system is: how do planets form in circumstellar disks around young stars? Because of the complex nature of the physical processes involved, multi-wavelength observations of large…
Circumstellar disks are an essential ingredient of the formation of low-mass stars. It is unclear, however, whether the accretion-disk paradigm can also account for the formation of stars more massive than about 10 solar masses, in which…
A clear understanding of the chemical processing of matter, as it is transferred from a molecular cloud to a planetary system, depends heavily on knowledge of the physical conditions endured by gas and dust as these accrete onto a disk and…
Protoplanetary disks dissipate rapidly after the central star forms, on time-scales comparable to those inferred for planet formation. In order to allow the formation of planets, disks must survive the dispersive effects of UV and X-ray…