Related papers: Multiple spiral arms in the disk around intermedia…

Context: Large cavities in disks are important testing grounds for the mechanisms proposed to drive disk evolution and dispersion, such as dynamical clearing by planets and photo-evaporation. Aims: We aim to resolve the large cavity in the…

Millimeter continuum spiral arms have so far only been detected in a handful of protoplanetary disks, and thus we have a limited understanding of the circumstances in which they can form. In particular, substructures in small disks…

Recent observations of protoplanetary disk have reported spiral structures that are potential signatures of embedded planets, and modeling efforts have shown that a single planet can excite multiple spiral arms, in contrast to conventional…

We use CO and H alpha velocity fields to study the gas kinematics in the spiral arms and interarms of M51 (NGC 5194), and fit the 2D velocity field to estimate the radial and tangential velocity components as a function of spiral phase (arm…

Context. The mechanisms governing the opening of cavities in transition disks are not fully understood. Several processes have been proposed but their occurrence rate is still unknown. Aims. We present spatially resolved observations of two…

Circumstellar asymmetries such as central warps have recently been shown to cast shadows on outer disks. We investigate the hydrodynamical consequences of such variable illumination on the outer regions of a transition disk, and the…

We report the results of ALMA observations of a protoplanetary disk surrounding the Herbig Ae star AB Aurigae. We obtained high-resolution (0.1"; 14 au) images in $^{12}$CO (J=2-1) emission and in dust continuum at the wavelength of 1.3 mm.…

We present new high resolution imaging of a light-scattering dust ring and halo around the young star HD 35841. Using spectroscopic and polarimetric data from the Gemini Planet Imager in H-band (1.6 microns), we detect the highly inclined…

Spiral arms in protoplanetary discs are thought to be linked to the presence of companions. We test the hypothesis that the double spiral arm morphology observed in the transition disc MWC 758 can be generated by an $\approx 10$ M$_{\rm…

We present new $H$-band scattered light images of the HD 32297 edge-on debris disk obtained with the Gemini Planet Imager (GPI). The disk is detected in total and polarized intensity down to a projected angular separation of 0.15", or 20au.…

More than a dozen young stars host spiral arms in their surrounding protoplanetary disks. The excitation mechanisms of such arms are under debate. The two leading hypotheses -- companion-disk interaction and gravitational instability (GI)…

ISO-Oph 2 is a wide-separation (240 au) binary system where the primary star harbors a massive (M$_{dust}$ $\sim$40 M$_{\oplus}$) ring-like disk with a dust cavity $\sim$50 au in radius and the secondary hosts a much lighter (M$_{dust}$…

We present high-resolution (30 mas or 130 au at 4.2 kpc) Atacama Large Millimeter/submillimeter Array observations at 1.2 mm of the disc around the forming O-type star AFGL 4176 mm1. The disc (AFGL 4176 mm1-main) has a radius of ~1000 au…

Spiral structures are important drivers of the secular evolution of disc galaxies, however, the origin of spiral arms and their effects on the development of galaxies remain mysterious. In this work, we present two three-armed spiral…

We find the star HD 34700 to be a double-lined spectroscopic binary. We also identify it as a weak-line T Tauri object The spectra of both components are very similar and both show the Li I feature at 6708 \AA. Strong arguments in favour of…

We present VLT/SPHERE adaptive optics imaging in Y$-$, J$-$, H$-$, and K-bands of the HD 100453 system and the discovery of a two-armed spiral structure in a disk extending to 0.37" ($\sim$42 AU) from the star, with highly symmetric arms to…

The disk surrounding SAO 206462, an 8 Myr-old Herbig Ae star, has recently been reported to exhibit spiral arms, an asymmetric dust continuum, and a dust-depleted inner cavity. By carrying out two-dimensional, two-fluid hydrodynamic…

Context. The SAO 206462 (HD 135344B) disk is one of the few known transitional disks showing asymmetric features in scattered light and thermal emission. Near-infrared scattered-light images revealed two bright outer spiral arms and an…

We use two-dimensional Fourier transformation to measure the pitch angle ($\varphi$) of the dominant spiral Fourier mode of well-defined spiral arms in 13 protoplanetary disks, making use of near-infrared scattered-light images of AB Aur,…

We present ALMA observations of a wide binary system in Orion, with projected separation 440 AU, in which we detect submillimeter emission from the protoplanetary disks around each star. Both disks appear moderately massive and have strong…