The radiation from stars and active galactic nuclei (AGNs) creates photodissociation regions
(PDRs) and X-ray-dominated regions (XDRs), where the chemistry or heating is dominated …

Of the over 150 different molecular species detected in the interstellar and circumstellar
media, approximately 50 contain 6 or more atoms. These molecules, labeled complex by …

This is a summary of the 2013 release of the plasma simulation code Cloudy. Cloudy
models the ionization, chemical, and thermal state of material that may be exposed to an …

We present the fifth release of the UMIST Database for Astrochemistry (UDfA). The new
reaction network contains 6173 gas-phase reactions, involving 467 species, 47 of which are …

Cold dark clouds are nearby members of the densest and coldest phase in the Galactic
interstellar medium, and represent the most accessible sites where stars like our Sun are …

▪ Abstract Our understanding of the evolution of organic molecules, and their voyage from
molecular clouds to the early solar system and Earth, has changed dramatically …

Aims. The production of saturated organic molecules in hot cores and corinos is not well
understood. The standard approach is to assume that, as temperatures heat up during star …

Chemical models used to study the chemical composition of the gas and the ices in the
interstellar medium are based on a network of chemical reactions and associated rate …

Molecular hydrogen is the most abundant molecule in the universe. It is the first one to form
and survive photo-dissociation in tenuous environments. Its formation involves catalytic …

Aims. Photodissociation by UV light is an important destruction mechanism for carbon
monoxide (CO) in many astrophysical environments, ranging from interstellar clouds to …