The PAH hypothesis after 25 years

Abstract

The infrared spectra of many galactic and extragalactic objects are dominated by emission features at 3.3, 6.2, 7.7, 8.6 and 11.2 μm. The carriers of these features remained a mystery for almost a decade, hence the bands were dubbed the unidentified infrared (UIR) bands. Since the mid-80's, the UIR bands are generally attributed to the IR fluorescence of Polycyclic Aromatic Hydrocarbon molecules (PAHs) upon absorption of UV photons -- the PAH hypothesis. Here we review the progress made over the past 25 years in understanding the UIR bands and their carriers.

13 pages, 7 figures. To appear in the proceedings of IAU symposium 280 "The Molecular Universe"

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Cited by in corpus (13)

• Unidentified Infrared Emission bands: PAHs or MAONs?
• VLA observations of ammonia in high-mass star formation regions
• Machine-learning prediction of infrared spectra of interstellar polycyclic aromatic hydrocarbons
• Laboratory Determination of the Infrared Band Strengths of Pyrene Frozen in Water Ice: Implications for the Composition of Interstellar Ices
• Photolysis-induced scrambling of PAHs as a mechanism for deuterium storage
• Gas-phase spectroscopy of photostable PAH ions from the mid- to far-infrared
• IR photofragmentation of the Phenyl Cation: Spectroscopy and Fragmentation Pathways
• Mid-infrared spectroscopy of the Andromeda galaxy
• Ion-Induced Molecular Growth in Clusters of Small Hydrocarbon Chains
• A multiwavelength investigation of the HII region S311: Young stellar population and star formation
• Spitzer/infrared spectrograph investigation of MIPSGAL 24 μm compact bubbles : Low resolution observations
• Machine-learning identified molecular fragments responsible for infrared emission features of polycyclic aromatic hydrocarbons
• IRMPD spectroscopy of a PAH cation using FELICE: The infrared spectrum and photodissociation of dibenzo[a,l]pyrene