Related papers: Planetary system around Vega
We present new sub-mm observations and modelling of Vega excess stars, using realistic dust grain models. For resolved disks, we find that different objects require very different dust grain properties in order to simultaneously fit the…
Planets have been detected in circumbinary orbits in several different systems, despite the additional challenges faced during their formation in such an environment. We investigate the possibility of planetary formation in the…
High-resolution sub-mm observations of some protoplanetary discs reveal non-asixymmetric features, which can often be interpreted as dust concentrations in vortices that form at the edges of gaps carved out by the embedded planets. We use…
Investigating the dynamical evolution of dust grains in proto-planetary disks is a key issue to understand how planets should form. We identify under which conditions dust settling can be constrained by high angular resolution observations…
The envelope of the red supergiant VY CMa has long been considered an extreme example of episodic mass loss that is possibly taking place in other cool and massive evolved stars. Recent submm observations of the envelope revealed massive…
HD 38206 is an A0V star in the Columba association, hosting a debris disc first discovered by IRAS. Further observations by Spitzer and Herschel showed that the disc has two components, likely analogous to the asteroid and Kuiper belts of…
We present the results of a coronagraphic imaging search for extra-solar planets around the young main-sequence stars, epsilon Eri and Vega. Concentrating the stellar light into the core of the point spread function by the adaptive optic…
We present new observations of the red supergiant VY CMa at 1.25 micron, 1.65 micron, 2.26 micron, 3.08 micron and 4.8 micron. Two complementary observational techniques were utilized: non-redundant aperture masking on the 10-m Keck-I…
The disc around PDS 70 hosts two directly imaged protoplanets in a gap. Previous VLT/SPHERE and recent James Webb Space Telescope/NIRCam observations have hinted at the presence of a third compact source in the same gap at ~13 au, interior…
This paper considers the distribution of dust which originates in the break-up of planetesimals that are trapped in resonance with a planet. There are three grain populations with different spatial distributions: (I) large grains have the…
The cold outer regions of protoplanetary disks are expected to contain a midplane-centered layer where gas-phase CO molecules freeze out and their overall abundance is low. The layer then manifests itself as a void in the channel maps of CO…
High levels of dust have been detected in the immediate vicinity of many stars, both young and old. A promising scenario to explain the presence of this short-lived dust is that these analogues to the Zodiacal cloud (or exozodis) are…
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%)…
The eccentric WR+O binary system WR 140 produces dust for a few months at intervals of 7.94 yrs coincident with periastron passage. We present the first resolved images of this dust shell, at binary phases ~0.039 and ~0.055, using aperture…
We present ALMA observations of the GQ Lup system, a young Sun-like star with a substellar mass companion in a wide-separation orbit. These observations of 870 $\mu$m continuum and CO J=3-2 line emission with beam size $\sim0.3''$ ($\sim45$…
We have searched for evidence of emission at 15 microns with ISOCAM and at 90 microns with ISOPHOT from dust orbiting six nearby pulsars, both in binaries and in isolation, located at distances between about 100 to 1000 pc. No emission was…
Recently, gas giant planets in nearly circular orbits with large semimajor axes ($a \sim$ 30--1000AU) have been detected by direct imaging. We have investigated orbital evolution in a formation scenario for such planets, based on core…
The nearby star Fomalhaut harbours a cold, moderately eccentric dust belt with a sharp inner edge near 133 au. A low-mass, common proper motion companion (Fom b), was discovered near the inner edge and was identified as a planet candidate…
The processes leading to dust formation and the subsequent role it plays in driving mass loss in cool evolved stars is an area of intense study. Here we present high resolution ALMA Science Verification data of the continuum emission around…
Planets embedded within dust disks may drive the formation of large scale clumpy dust structures by trapping dust into resonant orbits. Detection and subsequent modeling of the dust structures would help constrain the mass and orbit of the…