Related papers: PAHs in Comets: An Overview
The presence of carbon-chain molecules in the interstellar medium (ISM) has been known since the early 1970s and $>130$ such species have been identified to date, making up $\sim 43$% of the total of detected ISM molecules. They are…
Polycyclic Aromatic Hydrocarbons (PAHs) have long been invoked in the study of interstellar and protostellar sources, but the unambiguous identification of any individual PAH has proven elusive until very recently. As a result, the…
Emission from polycyclic aromatic hydrocarbons (PAHs), a commonly used indicator of star formation activity in galaxies, also has the potential to serve as an effective empirical tracer of molecular gas. We use a sample of 19 nearby…
I summarize the results of two recent studies, based on ISO and Spitzer mid-IR spectra of galaxies and Galactic regions, aimed at understanding the origins of the variations of the aromatic features among and inside galaxies. I show that…
We examine the annihilation of positrons on polycyclic aromatic hydrocarbon (PAH) molecules in interstellar medium conditions. We estimate the annihilation rates of positrons on PAHs by a semi-empirical approach. We show that PAHs can play…
Long-slit 8-13 um spectroscopy of the nebula around NGC 1333 SVS reveals spatial variations in the strength and shape of emission features which are probably produced by polycyclic aromatic hydrocarbons (PAHs). Close to SVS 3, the 11.2 um…
Polycyclic aromatic hydrocarbons (PAHs) appear to be ubiquitous in terrestrial atmosphere as well as in the interstellar medium (ISM). In the astrophysical context presence of PAHs is interpreted by the observations of mid-IR emission bands…
Polycyclic aromatic hydrocarbons (PAHs) are fundamental to understanding the interstellar medium (ISM) of several astrophysical objects. Normally present in Starburst (SB) galaxies, they have also been more frequently detected in active…
Virtually all detailed gas-phase models of the chemistry of dense interstellar clouds exclude polycyclic aromatic hydrocarbons (PAH's). This omission is unfortunate because from the few studies that have been done on the subject, it is…
Infrared (IR) absorption spectra of individual polycyclic aromatic hydrocarbons (PAHs) containing methyl (-CH3), methylene (>CH2), or diamond-like *CH groups and IR spectra of mixtures of methylated and hydrogenated PAHs prepared by gas…
Small organic molecules are thought to provide building blocks for the formation of complex interstellar polycyclic aromatic hydrocarbons (PAHs). However, the underlying chemical mechanisms remain unclear, particularly concerning the role…
Polycyclic Aromatic Hydrocarbons (PAHs) are organic molecules which comprise the smallest particles of dust in the interstellar medium (ISM). Due to their broad/complex emission profiles, obtaining kinematics is a challenge with traditional…
Polycyclic Aromatic Hydrocarbons are prevalent in the universe and interstellar medium but are primarily attributed to anthropogenic sources on Earth, such as fossil fuel combustion and firewood burning. Drawing upon the idea of PAHs as…
The high interstellar abundances of polycyclic aromatic hydrocarbons (PAHs) and their size distribution are the result of complex chemical processes implying dust, UV radiation, and the main gaseous components (H, C+, and O). These…
Polycyclic aromatic hydrocarbons (PAHs) have been observed in O-rich planetary nebulae towards the Galactic Bulge. This combination of oxygen-rich and carbon-rich material, known as dual-dust or mixed chemistry, is not expected to be seen…
We present a model for the hydrogenation states of Polycyclic Aromatic Hydrocarbons (PAHs) in the diffuse interstellar medium. First, we study the abundance of hydrogenation and charge states of PAHs due to photo-ionization,…
Polycyclic aromatic hydrocarbons (PAHs) play a key role in the chemical and hydrodynamical evolution of the atmospheres of exoplanets and planet-forming discs. If they can survive the planet formation process, PAHs are likely to be involved…
Polycyclic aromatic hydrocarbon (PAH) emission has been found in both starbursts and modestly starforming galaxies, but the relation between starforming activity and PAH luminosity is still a matter of debate. The different correlation…
Nitrogen-bearing polycyclic aromatic hydrocarbons (N-PAHs) are key precursors to complex organic molecules in both the interstellar medium and the nitrogen-rich planetary atmospheres. Despite the recent detections of nitrogen-functionalized…
Polycyclic Aromatic Hydrocarbons (PAHs) are ubiquitous complex molecules in the interstellar medium and are used as an indirect indicator of star-formation. On the other hand the ultraviolet (UV) emission from the young massive stars…