Related papers: A Flared, Orbiting, Dusty Disk Around HD 233517
Spectroscopic observations of white dwarfs reveal that many of them are polluted by exoplanetary material, whose bulk composition can be uniquely probed this way. We present a spectroscopic and photometric analysis of the DA white dwarf…
The structure of inner region of protoplanetary disks around young pre-main-sequence stars is still poorly understood. This part of the disk is shaped by various forces that influence dust and gas dynamics, and by dust sublimation, which…
A new class of pre-main sequence objects has been recently identified as pre-transitional disks. They present near-infrared excess coupled to a flux deficit at about 10 microns and a rising mid-infrared and far-infrared spectrum. These…
We report on interferometric observations of a face-on accretion system around the High-Mass young stellar object, G353.273+0.641. The innermost accretion system of 100 au radius was resolved in a 45 GHz continuum image taken with the…
Recently, a new planet candidate was discovered on direct images around the young (10-17 Myr) A-type star HD95086. The strong infrared excess of the system indicates that, similarly to HR8799, {\ss} Pic, and Fomalhaut, the star harbors a…
Excess infrared flux from white dwarf stars is likely to arise from a dusty debris disk or a cool companion. In this work, we present near-infrared spectroscopic observations with Keck/MOSFIRE, Gemini/GNIRS, and Gemini/Flamingos-2 of seven…
(ABRIDGED) Studies of debris disks have shown that most systems are analogous to the Edgeworth-Kuiper Belt. However a rare subset of sun-like stars possess dust which lies in the terrestrial planet region. In this study we aim to determine…
We report the detection of spatially-extended mid-infrared emission around the luminous embedded star IRc9 in OMC-1, as seen in 8.8, 11.7, and 18.3 micron images obtained with T-ReCS on Gemini South. The extended emission is asymmetric, and…
We report high precision, high cadence photometric measurements of the star HD 209458, which is known from radial velocity measurements to have a planetary mass companion in a close orbit. We detect two separate transit events at times that…
Theoretical arguments suggest that protoplanetary disks around young stars should start small and grow with the addition of high angular momentum material to reach the radii of several hundred AUs that characterize the disks around…
We report a Spitzer/IRAC search for infrared excesses around white dwarfs, including 14 newly-observed targets and 16 unpublished archived stars. We find a substantial infrared excess around two warm white dwarfs --- J220934.84+122336.5 and…
Isolated HAEBE stars are believed to represent an intermediate stage of objects between young stellar objects surrounded by massive, optically thick, gaseous and dusty disks and Vega like stars surrounded by debris disks. The star AB Aur is…
We report Spitzer/IRAC photometry of WD J0959-0200, a white dwarf that displays excess infrared radiation from a disk, likely produced by a tidally disrupted planetesimal. We find that in 2010, the fluxes in both 3.6 $\mu$m and 4.5 $\mu$m…
Spitzer Space Telescope IRAC 3-8 micron and AKARI IRC 2-4 micron photometry are reported for ten white dwarfs with photospheric heavy elements; nine relatively cool stars with photospheric calcium, and one hotter star with a peculiar high…
We present the first subarcsecond-resolution images at multiple mid-IR wavelengths of the thermally-emitting dust around the A0 star HD 32297. Our observations with T-ReCS at Gemini South reveal a nearly edge-on resolved disk at both 11.7…
We report the discovery of a rapidly rotating disk in a K-selected galaxy at z=1.34. Spatially resolved kinematics are determined from deep, moderate resolution Keck spectroscopy covering the redshifted [OII] 3727 line. A conservative…
Debris disks with extremely large infrared excesses (fractional luminosities $> 10^{-2}$) are rare. Those with ages between 30 and 130 Myr are of interest because their evolution has progressed well beyond that of protoplanetary disks…
We report the serendipitous discovery of a large edge-on protoplanetary disk associated with the infrared source IRAS 23077+6707. The disk's apparent size in the Pan-STARRS (PS1) images is ~11", making this one of the largest known disks on…
Spitzer IRAC observations of 15 metal-polluted white dwarfs reveal infrared excesses in the spectral energy distributions of HE 0110-5630, GD 61, and HE 1349-2305. All three of these stars have helium-dominated atmospheres, and their…
We study the dynamical origin of the structures observed in the scattered-light images of the resolved debris disk around HD 141569A. We explore the roles of radiation pressure from the central star, gas drag from the gas disk, and the…