Related papers: Evidence for a Snow Line Beyond the Transitional R…
Observations conducted using the Atacama Large Millimeter/submillimeter Array on the protoplanetary disk around TW Hya show the nitrogen fractionation of HCN molecules in HC$^{14}$N/HC$^{15}$N $\sim$120 at a radius of $\sim$20 AU. In this…
Transition disks have dust-depleted inner regions and may represent an intermediate step of an on-going disk dispersal process, where planet formation is probably in progress. Recent millimetre observations of transition disks reveal…
Water is detected in environments representing every stage of star and solar system formation, but its chemical evolution throughout these stages remains poorly constrained. Deuterium ratios offer a means of probing chemical links between…
The James Webb Space Telescope provides unprecedented information to study ices in protoplanetary disks. However, the saturation of ice bands in highly inclined disks hinders the measurement of ice abundances using classical spectroscopy.…
[abridged] Protoplanetary disks with AU-scale inner clearings, often referred to as transitional disks, provide a unique sample for understanding disk dissipation mechanisms and possible connections to planet formation. Observations of…
The sulfur chemistry in protoplanetary disks directly affects the composition and potential habitability of nascent planets, but its volatile inventory remains highly uncertain. Here, we present deep Atacama Large Millimeter/submillimeter…
We present a 0.5-2.2 micron scattered light spectrum of the circumstellar disk around TW Hya from a combination of spatially resolved HST STIS spectroscopy and NICMOS coronagraphic images of the disk. We investigate the morphology of the…
Investigating the molecular gas in the inner regions of protoplanetary disks provides insight into how the molecular disk environment changes during the transition from primordial to debris disk systems. We conduct a small survey of…
We have carried out a sensitive search for gas emission lines at infrared and millimeter wavelengths for a sample of 15 young sun-like stars selected from our dust disk survey with the Spitzer Space Telescope. We have used mid-infrared…
Planets are born in protostellar disks, which are now observed with enough resolution to address questions about internal gas flows. Candidates for driving the flows include magnetic forces, but ionization state estimates suggest much of…
We present an integrated thermal-chemical model for the atmosphere of the inner region of a protoplanetary disk that includes irradiation by both far ultraviolet (FUV) and X-ray radiation. We focus on how the photodissociation of water and…
Line ratios for different transitions of the same molecule have long been used as a probe of gas temperature. Here we use ALMA observations of the N2H+ J~=~1-0 and J~=~4-3 lines in the protoplanetary disk around TW Hya to derive the…
We present new observations of CO J=2-1 emission from the protoplanetary disk around TW Hya. Emission is detected out to 240 au (4") and found to exhibit azimuthal variations up to 20% beyond 180 au (3"), with the west side of the disk…
We report on the observation of hot water vapor (steam) in the inner AU of a young massive star located in the star-forming region IRAS 08576-4334. The water lines are detected in a medium resolution (R=10,000) K-band spectrum taken by the…
We analyze Herschel Space Observatory observations of 104 young stellar objects with protoplanetary disks in the ~1.5 Myr star-forming region Lynds 1641 (L1641) within the Orion A Molecular Cloud. We present spectral energy distributions…
Ultraviolet spectra of protoplanetary disks trace distributions of warm gas at radii where rocky planets form. We combine HST-COS observations of H2 and CO emission from 12 classical T Tauri stars to more extensively map inner disk surface…
Water ice is important for the evolution and preservation of life. Identifying the distribution of water ice in debris disks is therefore of great interest in the field of astrobiology. Furthermore, icy dust grains are expected to play…
Infrared spectroscopy, e.g., with JWST, provides a glimpse into the chemical inventory of the innermost region of protoplanetary discs, where terrestrial planets eventually form. The chemical make-up of regions inside snowlines is connected…
Planets are formed in disks around young stars. With an age of ~10 Myr, TW Hya is one of the nearest T Tauri stars that is still surrounded by a relatively massive disk. In addition a large number of molecules has been found in the TW Hya…
We investigate the effect of photodesorption on the snow line position at the surface of a protoplanetary disk around a Herbig Ae/Be star, motivated by the detection of water ice particles at the surface of the disk around HD142527 by Honda…