Related papers: LkCa 15: A Young Exoplanet Caught at Formation?
LkCa 15 hosts a pre-transitional disk as well as at least one accreting protoplanet orbiting in its gap. Previous disk observations have focused mainly on the outer disk, which is cleared inward of ~50 au. The planet candidates, on the…
The detection of planets in protoplanetary disks has proven to be extremely challenging. In contrast, rings and gaps, usually attributed to planet-disk interactions, have been found in virtually every large protoplanetary (Class II) disk…
The "Disk Substructures at High Angular Resolution Project" (DSHARP) has revealed an abundance and ubiquity of rings and gaps over a large sample of young planet-forming disks, which are hypothesised to be induced by the presence of forming…
Distinct gap features in the nearest protoplanetary disk, TW Hya (distance of 59.5$\pm$0.9 pc), may be signposts of ongoing planet formation. We performed long-exposure thermal infrared coronagraphic imaging observations to search for…
The growth of dust grains in protoplanetary disks is a necessary first step towards planet formation. This growth has been inferred via observations of thermal dust emission towards mature protoplanetary systems (age >2 million years) with…
Many extra-solar planets and a few planetary systems have been found indirectly by small periodic radial velocity variations around old nearby stars. The orbital characteristics of most of them are different from the planets in our solar…
PDS 70b is the most robustly detected young planet imaged in the gap of a transition disk so far, found at a separation of ~195 mas (~22 au) from its host star and at a position angle of about 155 deg. This system is therefore a unique…
The total disk gas mass and elemental C, N, O composition of protoplanetary disks are crucial ingredients for our understanding of planet formation. Measuring the gas mass is complicated, since H$_2$ cannot be detected in the cold bulk of…
Planet formation is one explanation for the partial clearing of dust observed in the disks of some T Tauri stars. Indeed studies using state-of-the-art high angular resolution techniques have very recently begun to observe planetary…
[Abridged] We map the stellar age distribution ($\lesssim 1$ Gyr) across a 6kpc$\,\times\,$6kpc area of the Galactic disc to constrain our Galaxy's recent star-formation history. Our modelling draws on the sample of Zari et al. (2021) that…
We present the highest angular resolution infrared monitoring of LkCa 15, a young solar analog hosting a transition disk. This system has been the subject of a number of direct imaging studies from the millimeter through the optical, which…
Planets form in disks around young stars. The planet formation process may start when the protostar and disk are still deeply embedded within their infalling envelope. However, unlike more evolved protoplanetary disks, the physical and…
In the past few years, several disks with inner holes that are empty of small dust grains have been detected and are known as transitional disks. Recently, Spitzer has identified a new class of "pre-transitional disks" with gaps; these…
When and how planets form in protoplanetary disks is still a topic of discussion. Exoplanet detection surveys and protoplanetary disk surveys are now providing results that allow us to have new insights. We collect the masses of confirmed…
Young circumstellar disks are of prime interest to understand the physical and chemical conditions under which planet formation takes place. Only very few detections of planet candidates within these disks exist, and most of them are…
LkCa 15 is an extensively studied star in the Taurus region known for its pre-transitional disk with a large inner cavity in dust continuum and normal gas accretion rate. The most popular hypothesis to explain the LkCa 15 data invokes one…
Discoveries of close-in young puffy (R$_{\rm p} \gtrsim$ 6 R$_\oplus$) planets raise the question of whether they are bona fide hot Jupiters or puffed-up Neptunes, potentially placing constraints on the formation location and timescale of…
We have developed a self-consistent model of the disk around the nearby 10 Myr old star TW Hya which matches the observed spectral energy distribution and 7mm images of the disk. The model requires a significant dust size evolution and a…
Flattened, rotating disks of cool dust and gas extending for tens to hundreds of AU are found around almost all low mass stars shortly after their birth. These disks generally persist for several Myr, during which time some material…
Directly imaged exoplanets in wide orbits challenge current gas giant formation theories. They need to form quickly and acquire enough material before the disk dissipates, which cannot be accommodated by in-situ formation by core accretion.…