Related papers: CO/H2 Abundance Ratio ~ 10^{-4} in a Protoplanetar…

The thermal structure of protoplanetary disks is a fundamental characteristic of the system that has wide reaching effects on disk evolution and planet formation. In this study, we constrain the 2D thermal structure of the protoplanetary…

Carbon monoxide (CO) is a poor tracer of H$_{2}$ in the diffuse interstellar medium (ISM), where most of the carbon is not incorporated into CO molecules unlike the situation at higher extinctions. We present a novel, indirect method to…

We report on a limited search for pure-rotational molecular hydrogen emission associated with young, pre-main-sequence stars. We looked for H_2 v=0 J = 3->1 and J = 4->2 emission in the mid-infrared using the Texas Echelon-Cross-Echelle…

Aims: To calculate chemistry and gas temperature of evolving protoplanetary disks with decreasing mass or dust settling, and to explore the sensitivity of gas-phase tracers. Methods: The density and dust temperature profiles for a range of…

[Abridged] The infrared ro-vibrational emission lines from organic molecules in the inner regions of protoplanetary disks are unique probes of the physical and chemical structure of planet forming regions and the processes that shape them.…

[Abridged] Snowlines in protoplanetary disks play an important role in planet formation and composition. Since the CO snowline is difficult to observe directly with CO emission, its location has been inferred in several disks from spatially…

According to traditional gas-phase chemical models, O2 should be abundant in molecular clouds, but until recently, attempts to detect interstellar O2 line emission with ground- and space-based observatories have failed. Following the…

Small organic molecules, such as C2H, HCN, and H2CO, are tracers of the C, N, and O budget in protoplanetary disks. We present high angular resolution (10-50 au) observations of C2H, HCN, and H2CO lines in five protoplanetary disks from the…

There are two major theoretical issues for the star formation law (the relation between the surface densities of molecular gas and star formation rate on a galaxy scale): (i) At low metallicity, it is not obvious that star-forming regions…

The chemical composition of planets is inherited by the distribution of the various molecular species in the protoplanetary disk at thetime of their formation. As of today, only a handful of disks has been imaged in multiple spectral lines…

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…

We present the detection and analysis of H2 absorption at z = 4.24 towards the bright quasar J0007-5705, observed with the Very Large Telescope as part of the ESPRESSO QUasar Absorption Line Survey (EQUALS). The high resolving power,…

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 work aims to understand which midplane conditions are probed by the DCO$^+$ emission in the disk around the Herbig Ae star HD 169142. We explore the sensitivity of the DCO$^+$ formation pathways to the gas temperature and the CO…

It is unclear how directly imaged substellar companions with masses near the deuterium burning limit form, because these objects are rare and their bulk properties are not diagnostic of their formation. In this paper we revisit this problem…

We present a study of gas-phase H2O and CO2 toward a sample of 14 massive protostars with the Short Wavelength Spectrometer (SWS) on board the Infrared Space Observatory (ISO). Modeling of the H2O spectra using a homogeneous model with a…

We measure the temperature of warm gas at planet-forming radii in the disk around the classical T Tauri star (CTTS) TW Hya by modelling the H2 fluorescence observed in HST/STIS and FUSE spectra. Strong Ly-alpha emission irradiates a warm…

We present detections of numerous 10-20 micron H2O emission lines from two protoplanetary disks around the T Tauri stars AS 205A and DR Tau, obtained using the InfraRed Spectrograph on the Spitzer Space Telescope. Follow-up 3-5 micron…

The MRS mode of the JWST-MIRI instrument gives insights into the chemical richness and complexity of the inner regions of planet-forming disks. Here, we analyse the H$_2$O-rich spectrum of the compact disk DR Tau. We probe the excitation…

Turbulence is the leading candidate for angular momentum transport in protoplanetary disks and therefore influences disk lifetimes and planet formation timescales. However, the turbulent properties of protoplanetary disks are poorly…