Related papers: Variable structure in the PDS70 disc and uncertain…
We report the discovery of a highly circularly polarized, variable, steep-spectrum pulsar in the Australian Square Kilometre Array Pathfinder (ASKAP) Variables and Slow Transients (VAST) survey. The pulsar is located about $1^\circ$ from…
We compared magnetograms from the KPVT/SPM, SoHO/MDI, SOLIS/VSM, and SDO/HMI with the aim of probing the effect on measured solar magnetism of the variation in instrument response with time, magnetogram signal level, and position on the…
We still do not understand how planets form, or why extra-solar planetary systems are so different from our own solar system. But the last few years have dramatically changed our view of the discs of gas and dust around young stars.…
The 1.33 mm survey of protoplanetary discs in the Taurus molecular cloud found annular gaps and rings to be common in extended sources (>~55 au), when their 1D visibility distributions were fit parametrically. We first demonstrate the…
In Montgomery (2009a), we show that accretion discs in binary systems could retrogradely precess by tidal torques like the Moon and the Sun on a tilted, spinning, non-spherical Earth. In addition, we show that the state of matter and the…
A fundamental question about the early evolution of low-mass protostars is when circumstellar disks may form. High angular resolution observations of molecular transitions in the (sub)millimeter wavelength windows make it possible to…
We present VLA 9 mm (33 GHz) observations of the HD 141569 system from semester 16A. The observations achieve a resolution of 0.25 arcsec ($\sim28$ au) and a sensitivity of $4.7~\mu \rm Jy~beam^{-1}$. We find (1) a $52\pm 5~\mu$Jy point…
HD141569 is a pre-main sequence star with a disc uniquely placed between protoplanetary and debris discs, similar to the older `hybrid' type discs. This work aims to place the mass and spatial structure of the disc midplane in the context…
Crescent-shaped asymmetries are common in millimetre observations of protoplanetary discs and are usually attributed to vortices or dust overdensities. However, they often appear on a single side of the major axis and roughly symmetric…
We present deep high-resolution ($\sim$50 mas, 8 au) ALMA 0.88 and 1.3 mm continuum observations of the LkCa 15 disk. The emission morphology shows an inner cavity and three dust rings at both wavelengths, but with slightly narrower rings…
We present high-resolution ($\lesssim 0.1''$) Hubble Space Telescope (HST)/Wide Field Camera 3 (WFC3) imaging of the near edge-on ($i{\sim}80^\circ$) protoplanetary disk IRAS 23077+6707 ("Dracula's Chivito") obtained across six broadband…
HD 163296 is one of the few protoplanetary discs displaying rings in the dust component. The present work uses ALMA observations of the 0.9 mm continuum emission having significantly better spatial resolution (~8 au) than previously…
A catalog of ionized gas velocity fields for a sample of 30 spiral and irregular galaxies of the Virgo cluster has been obtained by using three-dimensional optical data. The aim of this survey is to study the influence of high density…
Hydrodynamical simulations of planet-disk interactions suggest that planets may be responsible for a number of the sub-structures frequently observed in disks in both scattered light and dust thermal emission. Despite the ubiquity of these…
We report on monitoring observations of the TeV gamma-ray binary HESS J0632+057, which were carried out to constrain the interaction between the Be circumstellar disk and the compact object of unknown nature, and provide for the first time…
(Abridged) Transition disks are recognized by the absence of emission of small dust grains inside a radius of up to several 10s of AUs. Due to the lack of angular resolution and sensitivity, the gas content of such dust holes has not yet…
We analyze $^{12}$CO($J$=2-1), $^{13}$CO($J$=2-1), C$^{18}$O ($J$=2-1), and 1.3 mm continuum maps of the $\rho$ Ophiuchi A photo-dissociation region (PDR) obtained with ALMA. Layered structures of the three CO isotopologues with an angular…
We analyse spatially resolved ALMA observations at 0.9, 1.3, and 3.1 mm for the 26 brightest protoplanetary discs in the Lupus star-forming region. We characterise the discs multi-wavelength brightness profiles by fitting the…
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…
I review the observational evidence for spiral structure in the accretion discs of cataclysmic variables (CVs). Doppler tomography is ideally suited to resolve and map such co-rotating patterns and allows a straightforward comparison with…