Related papers: Warm Molecular Layers in Protoplanetary Disks
We present high-resolution $^{12}$CO and $^{13}$CO 2-1 ALMA observations, as well as optical and near-infrared spectroscopy, of the highly-inclined protoplanetary disk around SSTC2D J163131.2-242627. The spectral type we derive for the…
The distributions and abundances of molecules in protoplanetary disks are powerful tracers of the physical and chemical disk structures. The abundance ratios of HCN and its isomer HNC are known to be sensitive to gas temperature. Their line…
The gas temperature structure of protoplanetary disks is a key ingredient for interpreting various disk observations and for quantifying the subsequent evolution of these systems. The comparison of low- and mid-$J$ CO rotational lines is a…
Resolved molecular line observations are essential for gaining insight into the physical and chemical structure of protoplanetary disks, particularly in cold, dense regions where planets form and acquire their chemical compositions.…
The direct study of molecular gas in inner protoplanetary disks is complicated by uncertainties in the spatial distribution of the gas, the time-variability of the source, and the comparison of observations across a wide range of…
Carbon monoxide (CO) is the most commonly used tracer of molecular gas in the inner regions of protoplanetary disks. CO can be used to constrain the excitation and structure of the circumstellar environment. Absorption line spectroscopy…
Studying molecular species in protoplanetary disks is very useful to characterize the properties of these objects, which are the site of planet formation. We attempt to constrain the chemistry of S-bearing molecules in the cold parts of…
We develop a simple iterative scheme to include vertical turbulent mixing and diffusion in ProDiMo thermo-chemical models for protoplanetary discs. The models are carefully checked for convergence toward the time-independent solution of the…
The gas near the midplanes of planet-forming protostellar disks remains largely unprobed by observations due to the high optical depth of commonly observed molecules such as CO and H$_2$O. However, rotational emission lines from rare…
Observations from Spitzer and ground-based infrared spectroscopy reveal significant diversity in the molecular emission from the inner few AU of T Tauri disks. We explore theoretically the possible origin of this diversity by expanding on…
High spatial resolution CO observations of mid-inclination (30-75{\deg}) protoplanetary disks offer an opportunity to study the vertical distribution of CO emission and temperature. The asymmetry of line emission relative to the disk major…
We present an analysis of high-resolution spectroscopy of several bright T Tauri stars using the VLT/CRIRES and Keck/NIRSPEC spectrographs, revealing the first detections of emission from HCN and C2H2 in circumstellar disks at near-infrared…
We present time dependent chemical models for a dense and warm O-rich gas exposed to a strong far ultraviolet field aiming at exploring the formation of simple organic molecules in the inner regions of protoplanetary disks around T Tauri…
(Abridged) As the stellar X-ray and UV light penetration of a protoplanetary disk depends sensitively on the dust properties, trace molecular species like HCO+, HCN, and CN are expected to show marked differences from photoprocessing…
Aims: To constrain the ionization fraction in protoplanetary disks, we present new high-sensitivity interferometric observations of N$_2$H$^+$ in three disks surrounding DM Tau, LkCa 15, and MWC 480. Methods: We used the IRAM PdBI array to…
This is the second in a series of papers based on data from DISCS, a Submillimeter Array observing program aimed at spatially and spectrally resolving the chemical composition of 12 protoplanetary disks. We present data on six Southern sky…
We construct a new set of self-consistent analytical disk models by taking into account both viscous and radiative sources of thermal energy. We analyze the non-isothermal structure of the disk across the mid-plane for optically thick…
Observations of deuterium fractionation in the solar system, and in interstellar and circumstellar material, are commonly used to constrain the formation environment of volatiles. Toward protoplanetary disks, this approach has been limited…
We present MOCASSIN 2D photoionisation and dust radiative transfer models of a prototypical T Tauri disk irradiated by X-rays from the young pre-main sequence star. The calculations demonstrate a layer of hot gas reaching temperatures of…
H2CO is one of the most readily detected organic molecules in protoplanetary disks. Yet its distribution and dominant formation pathway(s) remain largely unconstrained. To address these issues, we present ALMA observations of two H2CO lines…