Related papers: Interferometric study on the temporal variability …
High-resolution, millimeter observations of disks at the protoplanetary stage reveal substructures such as gaps, rings, arcs, spirals, and cavities. While many protoplanetary disks host such substructures, only a few at the younger…
We analyse N-body simulations of star-forming regions to investigate the effects of external far and extreme ultra-violet photoevaporation from massive stars on protoplanetary discs. By varying the initial conditions of simulated…
As part of our continuing study of light variability in proto-planetary nebulae (PPNe), we present the results from a long-term study of nine southern hemisphere objects. We have monitored their light variations over a nine-year interval…
Forsterite is one of the crystalline dust species that is often observed in protoplanetary disks and solar system comets. Being absent in the interstellar medium, it must be produced during the disk lifetime. It can therefore serve as a…
Accretion variability is ubiquitous in YSOs. While large outbursts may strongly affect the disk, the effects of moderate bursts are less understood. We aim to study the physical response of the disk around the eccentric binary system DQ Tau…
The detection of rapid variability on a time-scale of hours in radio-quiet quasars (RQQSOs) could be a powerful discriminator between starburst, accretion disc and relativistic jet models of these sources. This paper contains an account of…
We present a database of $BVRI$ time-series photometry of the Orion Nebula Cluster obtained with two ground-based telescopes at different longitudes to provide simultaneous coverage with the 13-d Chandra observation of the cluster. The…
The transition between massive Class II circumstellar disks and Class III debris disks, with dust residuals, has not yet been clearly understood. Disks are expected to dissipate with time, and dust clearing in the inner regions can be the…
Dust-continuum observations of many protoplanetary disks reveal rings and gaps that are widely interpreted as evidence of ongoing planet formation. Here we present the first framework for inferring planet and disk parameters from such…
We present Very Large Array observations of the intermediate mass pre-main-sequence stars UX Ori and CQ Tau at 7mm, 3.6cm, and 6cm. These stars are members of the UX Ori variability class, where the origin of optical variability is thought…
The majority of the ultimate main-sequence mass of a star is assembled in the protostellar phase, where a forming star is embedded in an infalling envelope and encircled by a protoplanetary disk. Studying mass accretion in protostars is…
Systematic abundance differences that depend on the condensation temperatures of elements have been observed, in particular for stars similar to the Sun; solar twins and solar analogs. Similar differences have also recently been shown to…
The recent identification of several groups of young stars within 100 parsecs of the Sun has generated widespread interest. Given their proximity and possible age differences, these systems are ideally suited for detailed studies of star…
Extended low surface brightness emission has been identified in a number of protoplanetary disks, in tension with predictions of radial drift theory. We aim to investigate the nature and origin of faint, extended dust emission in the outer…
We predict how protoplanetary disks around low-mass young stars would appear in molecular lines observed with the ALMA interferometer. Our goal is to identify those molecules and transitions that can be used to probe and distinguish between…
The detection of a wide range of substructures such as rings, cavities and spirals has become a common outcome of high spatial resolution imaging of protoplanetary disks, both in the near-infrared scattered light and in the thermal…
We present multi-epoch Hubble Space Telescope imaging of the Great Disk Shadow in the Serpens star-forming region. The near-infrared images show strong variability of the disk shadow, revealing dynamics of the inner disk on time scales of…
We present a near-infrared (NIR) variability analysis for an 6\arcmin $\times$ 6\arcmin region, which encompasses the massive protocluster G286.21+0.17. The total sample comprises more than 5000 objects, of which 562 show signs of a…
The variability of young stellar objects is mostly driven by star-disk interactions. In long-term photometric monitoring of the accreting T Tauri star GI Tau, we detect extinction events with typical depths of $\Delta V \sim 2.5$ mag that…
We report on our project of coordinated VLTI/VLBA observations of the atmospheres and circumstellar environments of evolved stars. We illustrate in general the potential of interferometric measurements to study stellar atmospheres and…