Related papers: Complex structure of a proto-brown dwarf

The formation and earliest stages of protoplanetary discs remain poorly constrained by observations. ALMA will soon revolutionise this field. Therefore, it is important to provide predictions which will be valuable for the interpretation of…

We are undertaking an ALMA survey of molecular gas in galaxies selected for their strong HI absorption, so-called DLA/sub-DLA galaxies. Here we report CO(2-1) detection from a DLA galaxy at z = 0.716. We also present optical and…

We present results from our SMA observations and data analyses of the SMA archival data of the Class I protostar IRAS 04169+2702. The high-resolution (~0.5") $^{13}$CO (3-2) image cube shows a compact ($r$ ~< 100 au) structure with a…

FU Orionis-type objects are young, low-mass stars with large outbursts in visible light that last for several years or decades. They are thought to represent an evolutionary phase during the life of every young star when accretion from the…

We present a 4.5-4.85 micron R=5000 spectrum of the low mass class I young stellar object GSS 30 IRS1 (L=25L_sun) in the rho Ophiuchus core, observed with the infrared spectrometer (ISAAC) on the Very Large Telescope (VLT-UT1). Strong line…

(Abridged) In the low-mass star formation process, theoretical models predict that material from the infalling envelope could be shocked as it encounters the outer regions of the disk. Nevertheless, only a few protostars show evidence of…

Context. The study of protoplanetary disks is fundamental to understand their evolution and interaction with the surrounding environment, and to constrain planet formation mechanisms. Aims. We aim at characterising the young binary system…

Recent ALMA observations with 0''.1 resolution reveal characteristic substructures in circumstellar disks around young Class I sources, providing clues to the early stages of morphological disk evolution. In this paper, we applied PRIISM…

While most of the known debris discs present cold dust at tens of AU, a few young systems exhibit hot dust analogous to the Zodiacal dust. $\eta$ Corvi is particularly interesting as it is old and it has both, with its hot dust…

Context. "Snow lines", marking regions where abundant volatiles freeze out onto the surface of dust grains, play an important role for planet growth and bulk composition in protoplanetary disks. They can already be observed in the envelopes…

We analyze $^{12}$CO($J$=2-1), $^{13}$CO($J$=2-1), C$^{18}$O ($J$=2-1), and 1.3 mm continuum maps of the $\rho$ Ophiuchi A photo-dissociation region (PDR) obtained with ALMA. Layered structures of the three CO isotopologues with an angular…

Studying Class 0 objects is very important, as it allows to characterize dynamical processes at the onset of the star formation process, and to determine the physical mechanisms responsible for the outcome of the collapse. Observations of…

Prestellar cores are self-gravitating dense and cold structures within molecular clouds where future stars are born. They are expected, at the stage of transitioning to the protostellar phase, to harbor centrally concentrated dense…

ALMA has revealed that the millimetre dust structures of protoplanetary discs are extremely diverse. It has been proposed that the strength of H$_2$O emission in the inner disc particularly depends on the influx of icy pebbles from the…

The cold outer regions of protoplanetary disks are expected to contain a midplane-centered layer where gas-phase CO molecules freeze out and their overall abundance is low. The layer then manifests itself as a void in the channel maps of CO…

We are carrying out a physical and chemical study of the protostellar envelopes in a representative sample of IM Class 0 protostars. In our first paper (Crimier et al. 2010), we determined the physical structure (density-temperature radial…

We present ALMA observations of the largest protoplanetary disk in the Orion Nebula, 114-426. Detectable 345 GHz (856 micron) dust continuum is produced only in the 350 AU central region of the ~1000 AU diameter silhouette seen against the…

We present ALMA follow-up observations of two massive, early-stage core candidates, C1-N & C1-S, in Infrared Dark Cloud (IRDC) G028.37+00.07, which were previously identified by their N2D+(3-2) emission and show high levels of deuteration…

We investigate the origin of complex organic molecules (COMs) in the gas phase around the low-mass Class~0 protostar NGC1333-IRAS2A, to determine if the COM emission lines trace an embedded disk, shocks from the protostellar jet, or the…

The 30 Myr old A3-type star HD 21997 is one of the two known debris dust disks having a measurable amount of cold molecular gas. With the goal of understanding the physical state, origin, and evolution of the gas in young debris disks, we…