Related papers: HD139614: the interferometric case for a group-Ib …
Recent observations of the protoplanetary disk around the Herbig Be star HD 100546 show two bright features in infrared (H and L' bands) at about 50 AU, with one so far unexplained. We explore the observational signatures of a high mass…
We report the discovery of a circumstellar disk around the young A0 star, HR 4796, in thermal infrared imaging carried out at the W.M. Keck Observatory. By fitting a model of the emission from a flat dusty disk to an image at lambda=20.8…
We examine the ``puffed-up inner disk'' model (Dullemond, Dominik & Natta 2001), proposed for explaining the near-IR excess radiation from Herbig Ae/Be stars. Detailed model computations show that the observed near-IR excess requires more…
We present a study of the stellar parameters, distances and spectral energy distributions (SEDs) of HD 34282 and HD 141569, two pre-main sequence Herbig AeBe stars. Both objects have been reported to show `anomalous positions' in the HR…
We present spatially-resolved K- and L-band spectra (at spectral resolution R = 230 and R = 60, respectively) of MWC 419, a Herbig Ae/Be star. The data were obtained simultaneously with a new configuration of the 85-m baseline Keck…
Transition disks correspond to a short stage between the young protoplanetary phase and older debris phase. Along this evolutionary sequence, the gas component disappears leaving room for a dust-dominated environment where already-formed…
We analyse the main physical parameters and the circumstellar environment of the young Herbig Be star HD 98922. We present AMBER/VLTI high spectral resolution (R =12000) interferometric observations across the Br$\gamma$ line, accompanied…
Scattered light imaging has revealed nearly a dozen circumstellar disks around young Herbig Ae/Be stars$-$enabling studies of structures in the upper disk layers as potential signs of on-going planet formation. We present the first images…
Context: The evolution of a young protocluster depends on the relative spatial distributions and dynamics of both stars and gas. Aims: We study the distribution and properties of the gas and stars surrounding the luminous (10^4 L_sun)…
We have acquired sub-millimeter observations of 33 fields containing 37 Herbig Ae/Be (HAEBE) stars or potential HAEBE stars, including SCUBA maps of all but two of these stars. Nine target stars show extended dust emission. The other 18 are…
We present the complete sample of protoplanetary disks from the Gemini- Large Imaging with GPI Herbig/T-tauri Survey (Gemini-LIGHTS) which observed bright Herbig Ae/Be stars and T-Tauri stars in near-infrared polarized light to search for…
Giant planets grow by accreting gas through circumplanetary disks, but little is known about the timescale and mechanisms involved in the planet assembly process because few accreting protoplanets have been discovered. Recent visible and…
We investigate the physical structure of the gas component of the disk around the pre-main-sequence star HD169142. The 13CO and C18O J=2-1 line emission is observed from the disk with 1.4'' resolution using the Submillimeter Array. We adopt…
Young stars with masses 2-8 Suns, called the Herbig Ae and Be stars, often show a near-infrared excess too large to explain with a hydrostatically-supported circumstellar disk of gas and dust. At the same time the accretion flow carrying…
Using the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument, we present near-infrared K-band polarimetric imaging of nine Herbig stars selected from a volume-limited sample within 200 pc. We detect the disks around MWC 480,…
We present the first ground-based near-infrared image of the circumstellar disk around the post-Herbig Ae/Be star HD141569A initially detected with the HST. Observations were carried out in the near-IR (2.2 $\mu$m) at the Palomar 200-inch…
The morphological evolution of dusty disks around young (few Myr-old) stars is pivotal to better understand planet formation. Since both dust grains and the global disk geometry evolve on short timescale, high-resolution imaging of a sample…
In an effort to simultaneously study the gas and dust components of the disc surrounding the young Herbig Ae star HD 169142, we present far-IR observations obtained with the PACS instrument onboard the Herschel Space Observatory. This work…
We report high-resolution 1.6 $\micron$ polarized intensity ($PI$) images of the circumstellar disk around the Herbig Ae star AB Aur at a radial distance of 22 AU ($0."15$) up to 554 AU (3.$"$85), which have been obtained by the…
Herbig stars can be classified into group I and group II depending on the shape of the far-IR excess from the spectral energy distribution. This separation may be evolutionary and related to the vertical structure of these disks. We aim to…