Related papers: Adenine Abundance in a Collapsing Molecular Cloud
Cosmological N-body hydrodynamic computations following atomic and molecular chemistry (e$^-$, H, H$^+$, H$^-$, He, He$^+$, He$^{++}$, D, D$^+$, H$_2$, H$_2^+$, HD, HeH$^+$), gas cooling, star formation and production of heavy elements (C,…
The chemistry of molecular clouds has been studied for decades, with an increasingly general and sophisticated treatment of the reactions involved. Yet the treatment of turbulent diffusion has remained extremely sketchy, assuming simple…
We have investigated the role of molecular anion chemistry in pseudo-time dependent chemical models of dark clouds. With oxygen-rich elemental abundances, the addition of anions results in a slight improvement in the overall agreement…
We discuss the connection between the chemistry of dense interstellar clouds and those characteristics of cometary matter that could be remnants of it. The chemical evolution observed to occur in molecular clouds is summarized and a model…
The formation of stars is inextricably linked to the structure of their parental molecular clouds. Here we take a number of nearby giant molecular clouds (GMCs) and analyse their column density and mass distributions. This investigation is…
The study of primordial chemistry of molecules adresses a number of interesting questions pertaining to the thermal balance of collapsing molecular protoclouds. In numerous astrophysical cases molecular cooling and heating influence…
Abundance observations indicate the presence of often surprisingly large amounts of neutron capture (i.e., s- and r-process) elements in old Galactic halo and globular cluster stars. These observations provide insight into the nature of the…
The origin of life on Earth involves the early appearance of an information-containing molecule such as RNA. The basic building blocks of RNA could have been delivered by carbon-rich meteorites, or produced in situ by processes beginning…
The knowledge of isotopic and elemental abundances of the pristine solar system material provides a fundamental test of galactic chemical evolution models, while the composition of the solar photosphere is a reference pattern to understand…
Complex organic molecules, such as propylene (CH3CHCH2), are detected in molecular clouds (such as TMC1) with high fractional abundances (~2.10^{-9}, relative to hydrogen) that cannot be explained by gas-phase chemical reactions under…
Collisions between interstellar gas clouds are potentially an important mechanism for triggering star formation. This is because they are able to rapidly generate large masses of dense gas. Observationally, cloud collisions are often…
Context: Dark cloud chemical models usually predict large amounts of O2, often above observational limits. Aims: We investigate the reason for this discrepancy from a theoretical point of view, inspired by the studies of Jenkins and Whittet…
Detections of molecular lines, mainly from H2$ and CO, reveal molecular material in planetary nebulae. Observations of a variety of molecules suggest that the molecular composition in these objects differs from that found in interstellar…
Atoms and molecules, and in particular CO, are important coolants during the evolution of interstellar star-forming gas clouds. The presence of dust grains, which allow many chemical reactions to occur on their surfaces, strongly impacts…
In this work, we present the results of our investigation into the chemistry of Z- and E-cyanomethanimine (HNCHCN), both of which are possible precursors to the nucleobase adenine. Ab initio quantum chemical calculations for a number of…
After the recombination of Hydrogen, primordial molecules such as H_2, $HD$ can be formed.The formation of structures in the post-recombination gaseous medium is commonly explained by primordial density fluctuations. In a self-gravitating…
In order to understand the origin of observed molecular cloud properties, it is critical to understand how clouds interact with their environments during their formation, growth, and collapse. It has been suggested that accretion-driven…
We demonstrate that the observationally inferred rapid onset of star formation after parental molecular clouds have assembled can be achieved by flow-driven cloud formation of atomic gas, using our previous three-dimensional numerical…
In preparation for the HERMES chemical tagging survey of about a million Galactic FGK stars, we estimate the number of independent dimensions of the space defined by the stellar chemical element abundances [X/Fe]. [...] We explore…
Recent submillimeter and far-infrared wavelength observations of absorption in the rotational ground-state lines of various simple molecules against distant Galactic continuum sources have opened the possibility of studying the chemistry of…