Related papers: Chemical differences among collapsing low-mass pro…

Massive young stellar objects (MYSOs) with hot cores are classic sources of complex organic molecules. The origins of these molecules in such sources, as well as the small- and large-scale differentiation between nitrogen- and…

We investigate the presence of COMs in strongly UV-irradiated interstellar molecular gas. We have carried out a complete millimetre line survey using the IRAM30m telescope towards the edge of the Orion Bar photodissociation region (PDR),…

This paper presents a millimeter wavelength aperture-synthesis study of the spatial variations of the chemistry in the envelope around the deeply embedded low-mass protostar L483-mm on 1000 AU (5") scales. Lines of 8 molecular species…

Aims. We attempt to understand the presence of gas phase CO below its freezing temperature in circumstellar disks. We study two promising mechanisms to explain this phenomenon: turbulent mixing and photodesorption. Methods. We compute the…

Most stars, including the Sun, are born in rich stellar clusters containing massive stars. Therefore, the study of the chemical reservoir of massive star-forming regions is crucial to understand the basic chemical ingredients available at…

During star formation, the dense gas undergoes significant chemical evolution leading to the emergence of a rich variety of molecules associated with hot cores and hot corinos. The physical and chemical conditions are poorly constrained;…

The gas mass of protoplanetary disks, and the gas-to-dust ratio, are two key elements driving the evolution of these disks and the formation of planetary system. We explore here to what extent CO (or its isotopologues) can be used as a…

A prevailing theory for the interstellar production of complex organic molecules (COMs) involves formation on warm dust-grain surfaces, via the diffusion and reaction of radicals produced through grain-surface photodissociation of stable…

Carbon monoxide (CO) is the primary tracer for interstellar clouds where stars form, yet CO has never been detected in galaxies with an Oxygen abundance relative to Hydrogen less than 20% of solar, even though such low metallicity galaxies…

We have measured the deuterium fractionation (through the column density ratio N(N2D+)/N(N2H+)) and the CO depletion factor (ratio between expected and observed CO abundance) in a sample of 10 high-mass protostellar candidates, in order to…

There is a robust polyatomic chemistry in diffuse, partially-molecular interstellar gas that is readily accessible in absorption at radio/mm/sub-mm wavelengths. Accurate column densities are derived owing to the weak internal excitation, so…

Thanks to the advent of sensitive and broad bandwidth instrumentation, complex organic molecules (COMs) have been found in a wide variety of interstellar environments, not only in our Galaxy but also in external galaxies up to a redshift of…

In this review, I discuss recent detailed studies of individual molecular clouds in M33 in higher rotational transitions of CO, 13CO, and the fine structure line of atomic carbon. These data reveal that the temperature and density of the…

Recent studies have suggested that low-energy cosmic rays (CRs) may be accelerated inside molecular clouds by the shocks associated with star formation. We use a Monte Carlo transport code to model the propagation of CRs accelerated by…

Numerical simulations predict a considerable fraction of the missing baryons at redshift z ~ 0 resting in the so called warm-hot intergalactic medium (WHIM). The filaments and sheets of the WHIM have high temperatures 10^5 - 10^7 K) and a…

Resolving physical and chemical structures in the vicinity of a protostar is of fundamental importance for elucidating their evolution to a planetary system. In this context, we have conducted 1.2 mm observations toward the low-mass…

CO is commonly used as a tracer of the total gas mass in both the interstellar medium and in protoplanetary disks. Recently there has been much debate about the utility of CO as a mass tracer in disks. Observations of CO in protoplanetary…

Dense low mass cores in nearby clouds like Taurus and Auriga are some of the simplest sites currently forming stars like our Sun. Because of their simplicity and proximity, dense cores offer the clearest view of the different phases of star…

Observations of CO+ suggest column densities on the order 10^12 cm^-2 that can not be reproduced by many chemical models. CO+ is more likely to be destroyed than excited in collisions with hydrogen. An anomalous excitation mechanism may…

Young low-mass protostars often possess hot corinos, compact, hot and dense regions bright in interstellar Complex Organic Molecules (iCOMs). Besides of their prebiotic role, iCOMs can be used as a powerful tool to characterize the chemical…