Related papers: Creating the Radius Gap without Mass Loss
Planetary bodies form by accretion of smaller bodies. It has been suggested that a very efficient way to grow protoplanets is by accreting particles of size <<km (e.g., chondrules, boulders, or fragments of larger bodies) as they can be…
We address two outstanding issues in the sequential accretion scenario for gas giant planet formation, the retention of dust grains in the presence of gas drag and that of cores despite type I migration. The efficiency of these processes is…
We model the evolution of a Jupiter-mass protoplanet formed by the disk instability mechanism at various radial distances accounting for the presence of the disk. Using three different disk models, it is found that a newly-formed…
Extrasolar planet surveys have begun to detect gas giant planets in orbit around M dwarf stars. While the frequency of gas giant planets around M dwarfs so far appears to be lower than that around G dwarfs, it is clearly not zero. Previous…
The size frequency distribution of exoplanet radii between 1 and 4$R_{\oplus}$ is bimodal with peaks at $\sim$1.4 $R_{\oplus}$ and $\sim$2.4 $R_{\oplus}$, and a valley at $\sim$1.8$R_{\oplus}$. This radius valley separates two classes of…
We assess the potential of planet formation instigating the early formation of a photoevaporation driven gap, up to radii larger than typical for photoevaporation alone. For our investigation we make use of hydrodynamics models of…
Circumstellar discs likely have a short window when they are self-gravitating and prone to the effects of disc instability, but during this time the seeds of planet formation can be sown. It has long been argued that disc fragmentation can…
Recent observations by the {\it Kepler} space telescope have led to the discovery of more than 4000 exoplanet candidates consisting of many systems with Earth- to Neptune-sized objects that reside well inside the orbit of Mercury, around…
Recent ALMA observations indicate that while a range of disk sizes exist, typical disk radii are small, and that radial dust drift affects the distribution of solids in disks. Here we explore the consequences of these features in planet…
Using integral field spectroscopic data from the Mapping Nearby Galaxies at Apache Point Observatory survey, we investigate the spatially resolved properties and empirical relations of a star-forming galaxy and a non-star-forming galaxy…
Exoplanets observed by the {\it Kepler} telescope exhibit a bi-modal, radius distribution, which is known as the radius gap. We explore an origin of the radius gap, focusing on multi-planet systems. Our simple theoretical argument predicts…
Gas giants are thought to form by runaway accretion: an instability driven by the self-gravity of growing atmospheres that causes accretion rates to rise super-linearly with planet mass. Why runaway should stop at a Jupiter or any other…
Studies of internal structure of gas giant planets suggest that their envelopes are enriched with heavier elements than hydrogen and helium relative to their central stars. Such enrichment likely occurred by solid accretion during late…
Models of core accretion assume that in the radiative zones of accreting gas envelopes, radiation diffuses. But super-Earths/sub-Neptunes (1-4$R_\oplus$, 2-20$M_\oplus$) point to formation conditions that are optically thin: their modest…
We present the results of hydrodynamical simulations of the orbital evolution of planets undergoing runaway gas accretion in radiative discs. We consider accreting disc models with constant mass flux through the disc, and where radiative…
The radii and orbital periods of 4000+ confirmed/candidate exoplanets have been precisely measured by the Kepler mission. The radii show a bimodal distribution, with two peaks corresponding to smaller planets (likely rocky) and larger…
The radius valley, a bimodal feature in the size distribution of close-in small exoplanets, is widely interpreted as a signature of atmospheric loss and therefore provides a key constraint on the formation and atmospheric evolution of these…
It is reasonable to assume that the structure of a planet and the interior distribution of its components are determined by its formation history. We thus follow the growth of a planet from a small embryo through its subsequent evolution.…
(abridged) We find that a disk can supply a forming planet with mass at an essentially infinite rate ($\sim1$\mj/25 yr) so that a gap could form very quickly. We show that mass accretion rates faster than $\sim10^{-4}$\mj/yr are not…
Planet formation is directly linked to the birthing environment that protoplanetary disks provide. The disk properties determine whether a giant planet will form and how it evolves. The number of exoplanet and disk observations is…